COLOMBO, Sri Lanka (AP) — Sri Lanka police arrested three people in connection with warnings of a planned attack on Israel travelers visiting the Indian ocean island, a government minister said Thursday, a day after the authorities stepped up the security across the country as the U.S. issued a warning about a possible attack at a popular tourist destination.

Three Sri Lankans have been taken into custody and are now being interrogated, said Minister of Public Security and Foreign Affairs Vijitha Herath.

He declined to give further details, saying that would hamper the investigation.

Authorities said on Wednesday they had raised security around Arugam Bay, a popular surfing destination in the country’s east, after receiving intelligence from another country about a possible threat to Israeli travelers.

On Thursday, Herath said the information received did not include specifics but warned than an “attempt will be made to create disturbances” targeting places where Israel nationals conduct religious gatherings.

At present, 575 Israel nationals are in Sri Lanka, he said.

Also on Wednesday, the U.S. embassy in Sri Lanka alerted Americans to avoid the Arugam Bay area until further notice due to “credible information warning of an attack targeting popular tourist locations” in that area.

Israel’s government called on its citizens to leave the bay and other coastal areas in Sri Lanka’s south and west immediately.

The government said it has increased road blocks and vehicle checks and deployed army and navy troops, among other security measures to protect tourists who will be visiting the country during the year-end season.

Sri Lanka is slowly emerging from its worst economic crisis, and the tourism industry has been a main driver of its recovery.

Simultaneous suicide bomb attacks on three tourist hotels and three churches on Easter Sunday in 2019 caused a downturn in the industry and contributed to an economic collapse three years later.