Police evacuated a Roman Catholic church here Sunday where mourners had gathered in the wake of Friday's mass shooting at an elementary school that killed 20 children.

"The church has been evacuated," said a Connecticut state police trooper in front of the Saint Rose of Lima church, which was surrounded by law enforcement vehicles and SWAT team officers.

Armed police were seen by an AFP reporter conducting a search at a house next to the brown stone church.

Saint Rose of Lima was among several churches in Newtown filled by local residents seeking solace in the aftermath of Friday's shooting spree at Sandy Hook Elementary School in which six educators also died.

Others killed in the bloodbath included the 20-year-old gunman and his mother, found dead in the house they shared.