The Formula 1 season is scheduled to begin in Bahrain in March
Formula 1 boss Bernie Ecclestone has warned the season-opening Bahrain Grand Prix in March will be cancelled if unrest in the country continues.
F1 teams are concerned about the event after three people were killed overnight in clashes with police.
Ecclestone said he will make a decision on whether to cancel early next week.
He said: "If things stay as they are today, the answer is no. If it's not quietened down by Wednesday, I think we will have to cancel probably."
This weekend's GP2 Asia event at the Sakhir circuit has been cancelled after the unrest overnight, when
police moved in to clear a protest camp
in a square in the middle of the Bahrain capital Manama.
Virgin Racing team boss John Booth told BBC Sport: "It's obviously very disturbing and there is concern - that ramped up with the latest disturbance."
BBC Sport understands that teams are already considering whether to go ahead with the final pre-season test, which is due to be held in Bahrain from 3-6 March.
It does give you a lot of concerns but if we're informed it's safe to go, we'll go
John Booth Virgin team principal
It could be moved to one of the Spanish test tracks if the unrest continues.
Teams are expected to discuss what to do at this weekend's testing, which starts on Friday in Barcelona.
Booth said Virgin Racing would be led by Ecclestone's FOM company, motorsport governing body the FIA and the Bahraini authorities as they decide whether to travel to the race.
"If the local government, the FIA and FOM say it's safe to go, we'll go," he said.
"They will have people on the ground assessing the situation and they will be well informed on the risks.
"It does give you a lot of concerns but if we're informed it's safe to go, we'll go."
Thousands of overwhelmingly Shi'ite protesters have taken to Manama's streets this week demanding more say in the Gulf Arab kingdom where a Sunni Muslim family rules over a majority Shi'ite population.
On Thursday, the Bahraini authorities moved to try to end the unrest by banning the protests.
Ecclestone added: "I spoke to the Crown Prince (Salman bin Hamad bin Isa Al Khalifa) this morning. He doesn't know any more than you or I, but they're monitoring exactly what is going on."
The Crown Prince is the eldest son of the Bahrain King, Hamad ibn Isa Al Khalifa, and is the heir apparent and deputy supreme commander of the Bahrain defence force.
The teams are due to test in Bahrain a week before the race, which Booth admitted was an "added complication".
That means many F1 personnel are due to be in Bahrain for more than two weeks.
Our focus remains on delivering a successful grand prix and our priority is ensuring the wellbeing of everyone associated with this event
Sheikh Salman bin Isa Al Khalifa Bahrain circuit boss
Booth said a decision on whether the test would go ahead would need taking by 25 February, when the freight is scheduled to be sent out, and one on the race a week later, at the beginning of March.
Asked if the race could be held elsewhere, Booth said: "Impractical. Our sea freight, like every other team's, left for Bahrain a month ago, and a lot of the equipment in the sea freight is vital to the running of the cars. So to run it somewhere else would be very difficult."
On Thursday morning, GP2 practice was scrapped after medical staff at the track were assigned to hospitals in the capital, where protests are continuing.
Organisers later said the entire meeting was off "due to force majeure".
In a statement by the grand prix organisers later on Thursday, the track's chief executive officer, Sheikh Salman bin Isa Al Khalifa, said: "The safety of all Bahraini nationals, expats and overseas visitors is a priority at all times in the Kingdom and at the Bahrain International Circuit.
"Our focus at the present time remains on delivering another successful event in the form of the 2011 Bahrain Grand Prix, [and] we continue to monitor the situation very closely indeed in association with the relevant authorities.
"Our priority at this time is ensuring the wellbeing of everyone associated with this event, and we will respond appropriately to any further developments."
Speaking on Wednesday before the overnight clashes, Jean Todt, president of motorsport's world governing body, the FIA, said he was also monitoring developments in Bahrain.
"Of course, the essence of the FIA is safety; safety on the racing car, safety on the road, safety in our organisation," he said on a visit to Dublin.
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