LONDON (Reuters) - Stripped of his Bahraini citizenship and living in London exile, rights activist Sayed Ahmed AlWadaei says he speaks for the hundreds of opposition figures made voiceless by imprisonment back home.

Drawing on a network of activists, contacts, relatives of detainees and legal records, he publishes prolifically on developments in the Gulf island monarchy, an ally of the United States and Britain.

Scores of Bahraini exiles and dissidents live in London, but none campaigns more energetically against their native country’s crackdown on its critics.

Authorities in Bahrain tend to call such people - including AlWadaei himself - terrorists.

He says members of his own family have been detained and tortured in Bahrain in a bid to pressure him into silence.

“It’s crystal clear in my mind that the moment I stop my work, the reprisals against my family will stop,” AlWadaei, 31, told Reuters in an interview from the offices of the Bahrain Institute for Rights and Democracy (BIRD) in central London.

“It’s a matter of, will I allow them to break my will, will I allow them to break me by using those harsh tactics? Or will I make it costly for them, for their reputation and their partners to be associated with corrupt human rights abusers?” he said.

BIRD, which employs several British campaigners, receives funding from the U.S.-based National Endowment for Democracy and a UK foundation, the Sigrid Rausing Trust.

He seeks to shine a light on prison conditions and trials of detainees, such as the case of a mass sentencing on weapons charges this week of 58 people to penalties ranging from death to loss of citizenship. He decried it as a “travesty of justice”.

Bahrain, whose ruling family is Sunni Muslim, has seen sporadic unrest since 2011 when authorities crushed protests, mainly by the Shi’ite majority, demanding a bigger role in running the country.

AlWadaei was detained for taking part in the 2011 rallies. He accuses police of beating him and his jailers of torture and sexual harassment. He points to a large scar on his forehead.

Authorities accuse him of incitement to terrorism aimed at overthrowing Bahrain’s monarchy.

“DEMOCRACY VERSUS DICTATORSHIP”

In a response to a Reuters request for comment on AlWadaei’s accusations, a government spokesman said any allegations of abuses by security forces could be referred to an ombudsman and independently investigated.

The government says his mother-in-law and brother-in-law were sentenced in a fair trial to three years in jail in October for planting a “fake bomb” meant to taunt police.

“No one can be charged or prosecuted solely because of their family relations,” the government added.

AlWadaei believes the case against his relatives was motivated by his human rights work and especially a protest in which he took part in 2016 against the attendance of Bahrain’s king at a royal horse show in Britain.

A tiny country lying between regional arch-rivals Sunni Saudi Arabia and Shi’ite Iran, Bahrain is a key ally of Riyadh and the West.

It hosts the U.S.’s Fifth Fleet and soon also a new British naval base, its first permanent military presence in the Middle East since it withdrew from Bahrain and the rest of the Gulf region in 1971.

The government, citing years of deadly bombing and shooting attacks against its security forces, says it faces a militant threat backed by Tehran.

“They blame the situation on Iran to make it seem more of a sectarian problem rather than democracy versus dictatorship, which is the main context in Bahrain,” AlWadaei said.

He says his wife was detained and interrogated about his activities and movements as she and their young son were departing Bahrain’s airport to join AlWadaei in London.

The Bahraini government said she was not mistreated and dismissed AlWadaei’s accusations as “unsubstantiated.”

Because AlWadaei’s application process for “indefinite leave to remain” in Britain had not been decided by the time of his daughter’s birth last year, she has been rendered stateless like him for the time being.

Despite such challenges, he vows not to relent.

“I ... feel more determined that this injustice should stop, and no one, no human on earth, should be tortured or have his family go through reprisals simply because they stood up for human rights.”