An armed intruder allegedly tried to break into the Pennsylvania compound of exiled Turkish cleric Fethullah Gulen on Wednesday morning but was chased off by a security guard.
A Gulen spokesman said the guard fired a warning shot into the air and the suspect fled.
Pennsylvania state police searched the area but could not find the alleged intruder. A police statement said the investigation was continuing.
Gulen's group said it believed the Turkish government was behind the attempted break-in, noting that a spokesman for President Recep Tayyip Erdogan had threatened "overseas operations" against Gulen.
Gulen was a Turkish government ally, but he fled to the United States in 1999 when the government accused him of trying to undermine Turkish secularism.
Gulen has also accused the current government of corruption.
Turkey accused Gulen of orchestrating a failed coup in 2016 and has demanded the U.S. extradite him to Turkey to face charges of terrorism. The U.S. has refused.
VOA's Turkish service contributed to this report.