The security forces "managed over the past few weeks to destroy an organization, made of a cluster of cells, which is linked to the terrorist Daesh organization," the Saudi interior ministry announced Saturday, using the Arabic acronym for the Takfiri terror group.

Thirty-seven people were killed, including security personnel and civilians, and 120 more were wounded during the operation, said the ministry.

The alleged militants were taking part in a "plot managed from areas of unrest abroad, with the aim of sowing sectarian sedition and spreading chaos," it said, adding that the terrorist cells had connections to several attacks, including the bombings of Shia mosques in the Eastern Province.

It also claimed to have prevented the militants from launching several attacks during the holy month of Ramadan.

Most of the 431 detainees are Saudi nationals, 144 of whom face accusations of supporting the Takfiri group by "spreading the deviant ideology on the Internet and recruiting new members,” it noted.

Ninety-seven of those arrested were said to have had ties to a cell linked to 2014 attack on a Shia mosque in the village of Dalwa.

Some 190 of the suspects were allegedly involved in the Shia mosque attacks in the country’s Qatif and Dammam regions.

On November 3, 2014, masked gunmen stormed a group of Shia Muslims participating in a ceremony marking the martyrdom anniversary of Imam Hussein (PBUH), the third Shia Imam, in the village of Dalwah in al-Ahsa Governorate of Eastern Province, and opened fire as people were observing Ashura, the 10th day of the lunar month of Muharram.

On May 22, at least 21 people lost their lives and 97 others sustained injuries in a bomb attack against a Shia mosque in the Qatif region of Eastern Province.