Recent arson attacks and shootings in this violence-wracked South American nation are the work of a mastermind living in the United States, Guyanese President Bharrat Jagdeo alleged.

Jagdeo made the allegation late Friday, shortly after his administration submitted a request to the U.S. Embassy for assistance with the investigation.

"There is a terrorist mastermind who lives in the U.S.," Jagdeo told reporters. He declined to give more details.

Carol Horning, acting charge d'affaires at the U.S. Embassy, said Saturday that the Department of Justice is reviewing the request and will likely help out by checking U.S. phone records. She, too, did not disclose further details.

Three attackers dressed as police officers firebombed a wooden, colonial-era courthouse and a nearby school Wednesday, and later shot at two police stations, wounding one officer in the jaw and another in the ankle.

Witnesses identified two of the gunmen as inmates who recently escaped from jail where they were being held on suspicion of burning down the Health Ministry in July, police chief Henry Greene said.

Police searched villages along the southern edge of the capital, Georgetown, where they believe gang members who carried out the attacks are hiding.

Officials have detained and questioned numerous people in July's attack on the Health Ministry, but they have not given a possible motive.