Manufacturers have reacted quickly to Tuesday's terrorist attacks in the US.

Ford, while issuing a message of condolence to those affected by the tragedy, also insisted it was doing all it could to safeguard personnel, closing its plants in the US and Canada and its world headquarters yesterday in Dearborn, Michigan, on the orders of Nick Scheele, head of the company's North American operations.

Jac Nasser, Ford chief executive, went ahead with a meeting with the American Chamber of Commerce, yesterday, at its request. The chamber said it “wouldn't be intimidated by terrorists”.

Senior executives from Mazda were due to fly direct from Frankfurt on Friday morning to Heathrow to meet with staff and visit a small number of dealerships as well as doing press interviews in recognition of the company recently taking control of its UK distribution. The meetings have been cancelled, with the executives now going straight home to Japan. “We don't want to do any unnecessary flying,“ a Mazda spokesman said.

GM released this statement: “The sympathy and support of the company and its employees is with the American people. As part of a globally operating corporation, management and the workforce of General Motors in Europe express their deepest sympathy for the victims, their families and all those affected.”

As a token of solidarity, production at all of GM's European operations was halted at midday today for a minute's silence.

The mood at the Frankfurt motor show, which began yesterday, was also sombre. One of those there said: “There is none of the usual razzmattazz. It's been replaced by an eerie silence.”

The show was also hit by a bomb scare. Hall 3, the location of Ford Premier Automotive Group stands, plus Renault and Nissan, was evacuated briefly at about 9am local time.