Clashes hit Rio's Olympic Park
Striking construction workers and security personnel have clashed in Brazil at Rio de Janeiro's Olympic Park.
Rio Mais, the consortium building the venues for the 2016 Games, confirmed that random gunshots were fired as workers and security confronted each other. There were no reports of injuries.
The work stoppage involving more than 2,000 workers began on Thursday, and Rio Mais said it was unclear when work would resume.
"We are worried by the fact we are losing time," said Mario Andrada, spokesman for the Rio Olympic organising committee. "Beyond that, there is catch-up to do and we will have to move faster to make up whatever time we've lost."
Mr Andrada said he didn't have any details about the gunfire.
"Gunshots and violence worry us," he added. "But right now we don't know where this came from."
The labor dispute centres around which union represents the construction workers, and also involves benefits and working conditions.
The strike is sure to capture the attention of the International Olympic Committee executive board, which is meeting this week in the Turkish Mediterranean resort of Belek.
A team of IOC inspectors visiting Rio almost three weeks ago, headed by Olympic hurdle champion Nawal El Moutawakel, said the games faced "challenging deadlines".
IOC President Thomas Bach has repeated often that Rio "doesn't have a day to lose," and some fear it could face chronic delays similar to those hitting the upcoming World Cup, which begins in two months.
The strike adds to a growing list of problems confronting Rio organisers with the games just over two years away.
Construction on the second largest cluster of venues in northern Rio de Janeiro, in an area called Deodoro, has yet to begin. Work on the Olympic golf course has also been delayed.
Severe water pollution in Rio's Guanabara Bay, the venue for Olympic sailing, is a growing concern with a test event scheduled there in August.