An image provided by an activist shows Bahraini security forces during a raid on a sit-in demonstration on May 23, 2017. (AP)

A raid by government forces in Bahrain against a pro-opposition stronghold has left at least five people dead and hundreds detained in one of the deadliest crackdowns since protests erupted in 2011 against the Persian Gulf nation’s Western-backed monarchy.

Bahrain’s Interior Ministry said it carried out the raid Tuesday in the village of Duraz. It said officers came under attack, including from assailants armed with explosives. Opposition activists said that the police targeted a peaceful sit-in outside the home of Bahrain’s leading Shiite cleric and that the dead included an environmental activist.

Protests and clashes have flared for years in the tiny but strategic island nation between the Sunni-led monarchy and Bahrain’s majority Shiite population, which has complained of discrimination and other abuses. Bahrain hosts the U.S. Navy’s 5th Fleet.

The timing of the raid was striking, coming two days after President Trump publicly assured the king of Bahrain that their relationship would be free of the kind of “strain” that had occurred in the past — an apparent reference to the Obama administration’s periodic chiding of Bahrain over its human rights violations.

“Our countries have a wonderful relationship together, but there has been a little strain, but there won’t be strain with this administration,” Trump said during a photo session with the king, Hamad bin Isa al-Khalifa, at a conference in Riyadh, Saudi Arabia. 

Trump’s attendance at the ­Riyadh conference was largely aimed at winning back Persian Gulf allies that had bristled at President Barack Obama’s outreach to Shiite power Iran.

Trump’s widely anticipated speech, ostensibly about Islam and extremism, included assurances to the gulf’s Sunni states that “our friends will never question our support.”

In Bahrain, the government’s opponents viewed the conference and Trump’s appearance with the Bahraini monarch as providing tacit approval for the raid on Tuesday. 

“The killing of five protesters is a heinous crime enabled by the unconditional support of the Bahraini rulers’ key allies in Riyadh, Washington and London,” Sayed Ahmed Alwadaei, director of advocacy at the London-based Bahrain Institute for Rights and Democracy, said in a statement Wednesday. 

“This bloodshed — the blood that’s on their hands — will only continue unless it is met with severe consequences from the international community,” he said. 

In Washington, the State Department said that it is “troubled” by the clashes and urged restraint on all sides. “We urge the government of Bahrain to ensure those arrested are provided with access to counsel and that legal proceedings are conducted with transparency in accordance with due process,” spokeswoman Heather Nauert said in a statement.

Bahrain’s Ministry of Information Affairs did not immediately respond to a request for more details on the circumstances that led to the deaths or about the evolving U.S. relationship with Bahrain. A government statement released Wednesday said protesters refused an order to disperse and injured security personnel. It said the deaths were being investigated by the public prosecutor. 

Members of Bahrain’s Shiite majority have long protested what they say is widespread discrimination at the hands of the Sunni dynasty ruling the country. 

Political life and sectarian relations have steadily deteriorated since the government, with help from Persian Gulf allies, quashed a Shiite-led pro-democracy uprising in 2011. Since then, Bahrain’s most prominent opposition figures have been imprisoned, fled the country or are facing prosecution.

Officials in Bahrain have accused Iran of inciting unrest and increasingly aiding violent attacks against Bahrain’s security agents. 

 After the raid, Iran’s foreign minister, Mohammad Javad Zarif, denounced Bahrain and the United States for the raid. He wrote on Twitter that it was the “first concrete result of POTUS cozying up to despots in Riyadh: Deadly attack on peaceful protesters by emboldened Bahrain regime. Google it.”