Bahraini authorities said Tuesday they have launched a criminal investigation into statements made by the country's main Shiite opposition group, whose leader is already in jail.
The case is certain to exacerbate tensions between the tiny island kingdom's majority Shiites and the Sunni monarchy. It comes just days after the four-year anniversary of widespread anti-government protests dominated by the Shiite community seeking greater political rights in the Western-allied kingdom, which is home to the U.S. Navy's 5th Fleet.
The Interior Ministry said the probe involves statements made by the al-Wefaq group on its website and on Twitter "that are considered crimes that can be penalized by the law."
The group is suspected of "publicly inciting hatred against the government and distributing false news," and allegedly called for "illegal rallies and incited hatred against the Interior Ministry and a foreign country," it said.
The ministry did not provide further details. The case has been referred to the public prosecutor's office.
A senior member of al-Wefaq, Abdul-Jalil Khalil, said the group is legally registered with the authorities and doesn't have anything to hide.
"Our lawyers are assessing the allegations and they have not received any legal notice yet," he told The Associated Press. "Al-Wefaq abides by the legal requirements."
Al-Wefaq leader Ali Salman was arrested in December and has been charged with incitement to forcibly topple the government. He denies the allegations.
Bahrain has been on edge in recent days as opposition activists marked the anniversary of Arab Spring-inspired protests on Feb. 14, 2011.
Bahraini authorities backed by help from Saudi Arabia and the United Arab Emirates crushed the initial protests, but unrest continues in parts of the country. Activists armed with rocks and petrol bombs frequently block roads and fight police, and some small explosives have killed police.