Police: Maryland school shooter apparently was lovesick teen

This undated photo provided by the Willey family shows Jaelynn Willey. A teenager armed with a handgun shot and critically wounded Willey inside a Maryland school on Tuesday, March 20, 2018, and the shooter was killed when a school resource officer confronted him moments after the gunfire erupted. A third student was in good condition after he was shot. (Courtesy of the Willey family via AP)
Teachers and school employees depart Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018 in Great Mills, Md. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
This undated photo provided by the St. Mary's Sheriff's Office, shows Deputy First Class Blaine Gaskill, a school resource officer who engaged a shooter at Great Mills High School in Great Mills, Md., on Tuesday, March 20, 2018. It wasn't immediately clear whether the shooter took his own life or was killed by the officer's bullet, St. Mary's County Sheriff Tim Cameron said, but the Gaskill was credited with preventing any more loss of life. (St. Mary's Sheriff's Office via AP)
Teachers and school employees depart Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018 in Great Mills, Md. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
Deputies, federal agents and rescue personnel, converge on Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Susan Walsh)
Deputies, federal agents and rescue personnel, converge on Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Susan Walsh)
Police move students into a different area of Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Alex Brandon )
Two students and a mother leave Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. The shooting left at least three people injured including the shooter. (AP Photo/Alex Brandon )
A mother walks her daughter, a student from Great Mills High School, to the car as she picks her up from Leonardtown High School in Leonardtown, Md., Tuesday, March 20, 2018. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before a school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. (AP Photo/Carolyn Kaster)
A car is towed away on a flatbed tow-truck away from the parking lot of Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018, in Great Mills. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
A car is towed away on a flatbed tow-truck away from Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018, in Great Mills. (AP Photo/Alex Brandon)

Police: Maryland school shooter apparently was lovesick teen

This undated photo provided by the Willey family shows Jaelynn Willey. A teenager armed with a handgun shot and critically wounded Willey inside a Maryland school on Tuesday, March 20, 2018, and the shooter was killed when a school resource officer confronted him moments after the gunfire erupted. A third student was in good condition after he was shot. (Courtesy of the Willey family via AP)
Teachers and school employees depart Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018 in Great Mills, Md. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
This undated photo provided by the St. Mary's Sheriff's Office, shows Deputy First Class Blaine Gaskill, a school resource officer who engaged a shooter at Great Mills High School in Great Mills, Md., on Tuesday, March 20, 2018. It wasn't immediately clear whether the shooter took his own life or was killed by the officer's bullet, St. Mary's County Sheriff Tim Cameron said, but the Gaskill was credited with preventing any more loss of life. (St. Mary's Sheriff's Office via AP)
Teachers and school employees depart Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018 in Great Mills, Md. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
Deputies, federal agents and rescue personnel, converge on Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Susan Walsh)
Deputies, federal agents and rescue personnel, converge on Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Susan Walsh)
Police move students into a different area of Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. (AP Photo/Alex Brandon )
Two students and a mother leave Great Mills High School, the scene of a shooting, Tuesday morning, March 20, 2018 in Great Mills, Md. The shooting left at least three people injured including the shooter. (AP Photo/Alex Brandon )
A mother walks her daughter, a student from Great Mills High School, to the car as she picks her up from Leonardtown High School in Leonardtown, Md., Tuesday, March 20, 2018. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before a school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. (AP Photo/Carolyn Kaster)
A car is towed away on a flatbed tow-truck away from the parking lot of Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018, in Great Mills. A teenager wounded a girl and a boy inside his Maryland high school Tuesday before an armed school resource officer was able to intervene, and each of them fired one more round as the shooter was fatally wounded, a sheriff said. St. Mary's County Sheriff Tim Cameron said the student with the handgun was declared dead at a hospital, and the other two students were in critical condition. He said the officer was not harmed. (AP Photo/Alex Brandon)
A car is towed away on a flatbed tow-truck away from Great Mills High School, the scene of a shooting, Tuesday, March 20, 2018, in Great Mills. (AP Photo/Alex Brandon)