WASHINGTON (Reuters) - American University in Washington ended a lockdown on Wednesday prompted by reports of a man carrying a handgun near its campus, school officials said.

No shots were fired, an American University spokeswoman said, and the school had instructed students, faculty and staff on campus to shelter in place. There had been no immediate reports of people injured at the school, located about 4 miles (6.4 km) northwest of the White House.

U.S. school administrators have been on high alert following a series of deadly shootings in recent years, including the February massacre of 17 students and educators at a Florida high school.

“While the initial report indicated that this person was not on the AU campus, out of an abundance of caution, the American University Police Department issued an AU Alert and directed that the campus be put on lockdown,” the school said in a statement.

University police said they had searched the campus along with city police.

American University is located in the northwest corner of Washington, close to the border with Maryland.

Most students are away from U.S. college campuses during the summer, but American University hosts several camps, as well as summer classes, according to its website.