DALLAS (REUTERS) - Two gunmen opened fire at an anti-Islam art show featuring depictions of the Prophet Mohammad in Garland, Texas, near Dallas on Sunday.

They were later shot dead by police at the scene, a local CBS television affiliate and other local media reported, citing Garland police.

A guard was also shot in the leg during the incident, the Daily Telegraph reported.

The two genmen pulled up in a vehicle and shot a security guard. The men were then fatally shot by Garland police, The security officer was hospitalised, but his injuries were not believed to be life-threatening.

The gunmen were allegedly armed with explosives, the Telegraph reported,

The shooting was reported shortly before 7pm local time in the Texas city of Garland at the Curtis Culwell Centre, a special-events venue that hosts graduation ceremonies, concerts, trade shows, weddings and sporting events.

"Right when we were beginning to drive away, we heard gunshots," Ms Cynthia Belisle, who attended the event with a friend, told NBC News. "We thought they were fireworks, but they were not."

Garland police spokesman Joe Harn said that the area was evacuated and that participants were being taken away from the scene on buses.

In two Twitter posts attributed to Garland police, the CBS affiliate first reported that two men had "pulled up to the Culwell Center" and "started shooting", then reported the two suspects had been shot dead.

Another media outlet, WFAA-TV, reported that Garland police had shot and killed the two gunmen and that one officer was wounded.

NBC News reported that there was a "Draw Muhammad" contest at the venue, which was heavily policed. The New York-based American Freedom Defence Initiative was hosting the contest that would award US$10,000 (S$13,300) for the best cartoon depicting Prophet Muhammad at the venue.

The Dallas Morning News reported that critics of the Muhammad Art Exhibit and Contest, had condemned the event as an attack on Islam, but that organisers had said they were merely exercising their right of free expression.

The contest was described as a "free speech" event by its sponsor. It featured Dutch politician Geert Wilders, who is known for his anti-Muslim views, as its speaker.

There was no official word yet on the shooting or on the identity of the gunmen.

Western art depicting the Prophet has sometimes angered Muslims and provoked threats from radicals. In January, Islamist gunmen attacked the Paris offices of the French satirical magazine Charlie Hebdo in revenge for its cartoons of the Prophet, killing 12 people.