Boris Johnson and Keir Starmer have laid flowers at the scene of the killing of David Amess, the Conservative backbench MP.

The party leaders were joined by Priti Patel and Lindsay Hoyle, the Commons Speaker, at Belfairs Methodist church on Saturday morning to lay wreaths in tribute to Amess, who was stabbed to death on Friday while meeting constituents.

Starmer stood side by side with the prime minister outside the church, PA Media reported.

The politicians went up individually to the front of the church to pay their respects before returning to their vehicles without stopping to talk to reporters.

They joined a steady stream of people arriving at the church with flowers. Samantha Macdonald, 44, who lives in the area, wept as she recalled meeting Amess when he came to her school when she was 12.

“He was always so involved with the community, so accessible as well – prided himself on being accessible,” she said. “He knew every headteacher’s name of every school in his constituency. My 13-year-old daughter absolutely loved him.”

Patel, the home secretary, later visited Southend-on-Sea police station, where she spoke to officers investigating Amess’s death. A 25-year-old man has been arrested on suspicion of murder.

Speaking outside the police station, Patel paid tribute to Amess, who she described as a “man of the people”, and insisted that MPs would not be deterred from meeting the public.

“We will carry on,” Patel said. “We live in an open society and democracy; we cannot be cowed by any individual or any motivation, people with motives, to stop us from functioning to serve our elected democracy.”

Amess “was killed doing a job that he loves, serving his own constituents as an elected democratic member”, Patel said. “Of course, acts of this [kind] are absolutely wrong and we cannot let that get in the way of our functioning democracy.

“So that is why there are measures under way right now – I convened meetings yesterday, I’ve been with the Speaker of the house, and with the police and our security services to make sure that all measures are being put in place for the security of MPs so that they can carry on with their duties as elected democratic members.”

A National Police Chiefs’ Council spokesperson earlier said every MP would be contacted to discuss their security arrangements.