AFTER a couple of days off to indulge his passion for the architecture of Charles Rennie Mackintosh, it was back to work for Brad Pitt yesterday and another day of running away from zombies.

The actor, who has been in Glasgow since last week shooting scenes for his new film World War Z, spent the day filming the aftermath of a dramatic crash on the corner of George Square and George Street.

The city centre streets have been dressed with props, including signs and traffic lights, to make them look like Philadelphia where the post-apocalyptic film is set.

As hundreds of extras -- including the former Celtic player Bobby Petta -- ran screaming around him, Brad emerged from a smashed-up silver Volvo, helping a girl believed to be his on-screen daughter.

Stuntmen had earlier staged a spectacular crash between the Volvo and an ambulance at the bottom of North Frederick Street.

Other extras, dressed as US soldiers and holding replica M-16s, stood by Humvee military vehicles.

The action around George Square was a return to the set for Pitt after a break in his schedule during which he visited Mackintosh’s Hill House in Helensburgh. Pitt is known to be a fan of the Glasgow architect.

Pitt’s partner, the actress Angelina Jolie, also visited the Dumfries headquarters of the landmine charity, the Halo Trust, of which she is a patron.

Some of Pitt’s scenes yesterday had been due to be filmed on Sunday but the good weather meant they had to be postponed as the film takes place on a rainy day. While there were heavy showers in Glasgow yesterday, the crew had earlier been forced to douse the streets with water to create the illusion it had just been raining.

World War Z, which is due for release next year, is based on the novel World War Z: An Oral History of the Zombie War, written by Max Brooks.

The author will be in Glasgow tomorrow to watch some of the action on the set of the film adaptation of his book. He will also be signing copies of his book at Waterstone’s in Sauchiehall Street from 2pm until 3.30pm, and Forbidden Planet, Buchanan Street at 5.30pm.

Mr Brooks, who is the son of the comic actor and director Mel Brooks, wrote the book in 2006 as a sequel to The Zombie Survival Guide, which has sold more than one million copies.