The Lynn man fatally shot by police Sunday was among a group of men who were about to launch an armed home ­invasion, Essex District Attorney Jonathan W. Blodgett said Wednesday.

Blodgett said in a statement that as part of a joint federal, state, and local investigation, investigators had “received ­reliable information” that Brandon Payne, 23, and others were “in the process of initiating an armed home invasion.”

“Acting on this information, members of the Massachusetts State Police Gang Unit and the Lynn Police Depart­ment acted swiftly to prevent this potentially deadly home invasion by attempting to stop the vehicles,” Blodgett said in the statement.

Authorities said Monday that Payne was shot after he rammed his car into a police cruiser when officers tried to stop his car and another Sunday at about 9:30 p.m. at ­Ingalls and Chatham streets in Lynn.

Authorities had previously said only that police had witnessed a possible illegal gun exchange between occupants of the two vehicles before trying to stop the cars. A spokeswoman for Blodgett, Carrie Kimball Monahan, said Wednesday that the infor­mation about the suspected home invasion “was not able to be shared” until now.

Three other men who were in the two cars are facing charges. A fourth suspect is being sought.

An Essex prosecutor said at the arraignment of the three men Monday that police were “fearing for their lives.” Author­ities said three guns were removed from the two vehicles.

The district attorney’s ­office continues to investigate whether the shooting was justified. Blodgett said a complete report will be released once the investigation is complete.