The Justice Department began an investigation Friday into the shooting death of the Kansas doctor who provided late-term abortions and will seek to determine if more than one person was involved in the crime, department officials said.

The federal investigation into the killing of the doctor, George R. Tiller, who was shot on Sunday in the foyer of his church in Wichita, will also include a review of evidence and an assessment of possible violations of the federal Freedom of Access to Clinic Entrances Act, the department said.

After vandalism at the Wichita clinic in May, one of Dr. Tiller’s lawyers sent a letter to federal authorities requesting an investigation for potential violations of the freedom-of-access act.

“The Department of Justice will work tirelessly to determine the full involvement of any and all actors in this horrible crime,” Loretta King, the acting assistant attorney general for the civil rights division, said in a written statement.