Saudi Arabia said Saturday it broke up planned Islamic State attacks in the kingdom, announcing it has arrested over 400 people in its raids.

In a statement Saturday carried on the official state news agency, the Interior Ministry also accused those arrested over the "past few weeks" of conducting several attacks, including an Islamic State-claimed suicide bomb in May that killed 21 people in the village of al-Qudeeh, in the oil-rich eastern Qatif region. It was the deadliest militant assault in the kingdom in more than a decade.

It also blamed them for the November shooting and killing of eight worshippers in the eastern Saudi Arabian village of al-Ahsa.

The statement said the arrested men were also behind another attack in late May, when a suicide bomber disguised as a woman blew himself up in the parking lot of a Shiite mosque during Friday prayers, killing four people.

The Interior Ministry said that in June they thwarted a suicide bomb attack on a large mosque in eastern Saudi Arabia that can hold 3,000 worshippers, along with multiple planned attacks on other mosques and diplomatic and security bodies.

Those arrested were also behind a number of militant websites used in recruiting, the ministry said.

Saudi Arabia branded the Islamic State group a terrorist organization last year and has joined the U.S.-led coalition targeting it in Syria and Iraq.

The announcement came a day after an attack by the Islamic State group on a crowded marketplace in Iraq's eastern Diyala province killed 115 people, including women and children, in one of the deadliest single attacks in the country in the past decade.