The Allen Avenue Extension, which connects Portland with Falmouth, remained closed to traffic Sunday evening while emergency responders continued their search for a person last seen entering the Presumpscot River late Sunday afternoon.

That person did not resurface prompting Falmouth police to shut down the road that allows traffic to pass over the river. Maine Marine Patrol boats have also been deployed, according to a dispatcher for the Falmouth Police Department. Divers and a helicopter have also been used.

Emergency responders were notified by the swimmer’s friends around 4:45 p.m. Allen Avenue Extension between Pleasant Road and Falls Road was subsequently closed to traffic.

Two parks, both in Falmouth, are located on the north side of the Presumpcot River Bridge, which is where search teams are based.

Walton Park is a 4.4 acre parcel of land adjacent to the Presumpscot River. It features an ADA compliant trail that leads to water’s edge from the parking lot. There is a pier, gangway and float, which are available for boat access to the river. Located across the street is the Presumpscot Falls Park.

It was not clear how long the search would last late Sunday.