Activists are calling on broadcasters, including the BBC and Sky, to boycott the Bahrain Grand Prix as organisers face mounting pressure over the Formula One race due to be staged in the troubled Gulf state on 22 April.

Prominent human rights campaigners said they wanted broadcasters organisations not to air the race, if it went ahead, given recent events in the country.

The call comes as sources told BBC Sport that a number of teams have indicated they expect the race to be called off amid safety concerns following a recent spike in violence in Bahrain over calls for democratic reform.

Formula One boss Bernie Ecclestone said on Tuesday that no teams had expressed concerns to him, but added it would be a breach of contract if any team did pull out.

But the Formula One Teams' Association (Fota) has said the decision over whether or not to cancel is one for the sport's governing body, the Fédération Internationale de l'Automobile (FIA). The teams are due to meet Ecclestone in Shanghai at the Chinese Grand Prix this weekend.

Concerns over the fate of an imprisoned anti-government activist, as well as continued demands for reforms from Bahrain's Shia majority from its Sunni monarchy, have led to calls for the race to be cancelled. Abdulhadi al-Khawaja, 52, has been on hunger strike for 63 days.

His daughter Zainab al-Khawaja, told the Guardian: "If the Formula One does come to Bahrain, despite calls from the Bahraini people and activists for it to be cancelled, then we would like to see that there are people supporting our cause, and who would not broadcast this race.

"Bringing Formula One, putting all these ads everywhere, celebration, celebration, celebration, while people are suffocating in their villages from teargas, while a marcher dies just two weeks ago and while my father is dying in a military hospital is just sending the message to the people of Bahrain that nothing has changed."

Dr Ala'a Shehabi, an activist who has been in communication with Ecclestone over the race's future, said she was writing to the BBC and Sky. "Formula One is all about advertising, marketing, it's more about the commercial side than the actual sport itself.

"So we know that in broadcasting, you're encouraging all of the commercial interests in the sport which puts finance over human rights. That is what the major moral issue is here. If we can target the broadcasters, we can at least cut some of the possibility of profits made from advertising, at least … We will be asking them [the broadcasters] to examine their endorsement of Formula One. If they stay unquestioned, they won't think twice about broadcasting."

The BBC, which shares broadcast rights in the UK with Sky until 2018, said in a statement: "As the race had been officially sanctioned by the FIA we would expect to cover the events as part of our contractual obligations. However, we are in regular communication with the FIA and will be monitoring the situation closely."

Sky had no comment.

Bahrain has a contract until 2016 to stage the grand prix, but rules state that any race cancelled two years running cannot be put back on the calender. The authorities, which cancelled the race in 2011 owing to political unrest during the Arab spring, show no indication of doing so this year.

Bahrain's interior ministry said seven policemen were injured by a homemade bomb on Monday in Eker, a village outside the capital, Manama. The government blamed protesters calling for Khawaja's release, and described the bombing as "an act of terrorism".

On Wednesday, the Associated Press reported that mobs with iron rods and sticks ransacked a supermarket belonging to a major Shia-owned business group. The agency said the attack appeared linked to a series of reprisals and intimidation by suspected Sunni groups angered by the 14-month-old uprising.

Fears for the health of Khawaja, a Bahrain-Danish human rights activist and co-founder of the Bahrain Human Rights Centre who was imprisoned a year ago, grew after his family and lawyer said they had been denied contact for three days earlier this week. Amnesty International has called for his release, and UN secretary general Ban Ki-moon, has urged Bahrain to re-consider its refusal to allow Denmark to take custody of him.

His daughter said she "got a very short call" from her father on Wednesday, after he agreed to "drink some water" if they allowed him to "let us know he was still alive".

"He sounded very weak. We are happy we heard his voice, but we don't know where it is going to go from here. Today is the 63rd day of his hunger strike," she said.