Four members of the Sahara Force India F1 team were caught up in the unrest in Bahrain on Wednesday night.

The incident occurred as they travelled back from the Bahrain International Circuit to their hotel. The vehicle they were travelling in got stuck in traffic, as police and protesters clashed on the main road to the capital Manama. A firebomb then landed near the car. Although no one was injured, two team members - one of whom was involved in the incident - have since asked to return home.

Bahrain International Circuit chairman Zayed R Alzayani told Autosport: "It was an isolated incident, and my wife was involved too.

"The protestors were not targeting the cars, they just happened to be there. Nobody was injured.

"I don't command the police; they know what to do better than I do. I have a race to run."

The FIA's decision to hold the race meanwhile has come under further scrutiny, after the All Party Parliamentary Group for Democracy in Bahrain wrote to the major sponsors involved in F1 and urged them to boycott this weekend's event.

An excerpt from the letter, published by the Daily Telegraph, read: "Should the Bahrain Grand Prix go ahead, the sport and its associates run the risk of looking greedy and out of touch with the reality of the situation.

"We are most alarmed that you see no grounds to sever your brand and save its reputation from a totalitarian regime."

"I think it is a very silly decision they [the FIA] have made," Labour MP Andy Slaughter, who is Group Chairman of the All Party Parliamentary Group for Democracy in Bahrain, added in an interview with BBC Sport. "Nobody can deny the problems we had last year in Bahrain are continuing. I think that's very clear. There is no more reason for going ahead than last year.

"It is very naive to say [the F1 race is only about sport]... even if you're not interested in the wider political situation there, there are still humanitarian issues here."