More civil unrest in Bahrain will intensify speculation that the island Kingdom's return to the F1 calendar in 2012 will be called off.2011 pre-season testing and the Grand Prix at the Sakhir circuit were cancelled due to a political uprising in which the government was later found to have used excessive force against its people.Bernie Ecclestone said: "We have been assured that this is not what's happening."What did the report say? Yes, there were instances or whatever, but I wanted to go out there. I was happy to go. I'd like to go into the prison or the hospital or whatever and ask 'What actually happened?'" he said. "I hope we go to Bahrain (in 2012) and that there's no trouble - the race goes on, the public is happy and there is no drama. That's what I hope."'OBVIOUSLY A PROBLEM'Those hopes might have been dashed by reports that a Bahraini woman died after inhaling tear gas fired during a demonstration near the capital Manama in January 2012, the third death since November, 2011; a teenager reportedly dying after a tear gas canister hit him on the head in December 2011 and another was hit by a police vehicle a month earlier.Ecclestone was asked if he would consider calling off the 2012 race if there was proof that Bahrain's problems were persisting.Ecclestone said: "We'd have to give it some serious thought then but we've been to Argentina when there's been big dramas. There's been dramas in Brazil."I think you can look anywhere now and it's not all good."Ecclestone told Al Jazeera in December: "There obviously is a problem and I'm quite sure that eventually they'll get to the bottom of it and sort it out."The Bahrain F1 GP is scheduled as the fourth of 20 races in 2012.