US officials said on Sunday that they cannot confirm Saudi news report that American citizens were among the 33 suspects detained over terrorism charges in Saudi Arabia over the past week.
The Saudi Gazette newspaper reported that four Americans were arrested on Monday and five others over the past four days, citing an unidentified source.
The arrests also reportedly included 14 Saudis, three Yemenis, two Syrians, an Indonesian, a Filipino, a United Arab Emirates citizen, a Palestinian and a citizen of Kazakhstan.
Six US officials told Reuters that the US government could not confirm if Americans were among the suspects who were detained. However, one of the officials said US authorities were still checking names against databases. Neither official was authorised to speak publicly.
Reports did not say if any of the "terror suspects" were linked to DAESH , which has claimed several deadly attacks against security forces in the kingdom since last year.
The Saudi Gazette said some 532 DAESH suspects accused of plotting attacks in the kingdom are being questioned ahead of their trial at the criminal court in Riyadh.
They are members of six cells arrested in "pre-emptive" raids across the kingdom and include a Saudi woman and a Filipino, the paper said.
Also on Sunday, the Saudi Interior Ministry said that they were searching for nine suspects allegedly involved in an August suicide bombing that targeted a mosque inside a police headquarters, killing 15 people. DAESH had claimed responsibility for the attack in the southern city of Abha.
The ministry said in a statement that three other suspects, including a member of the kingdom's special forces, had been arrested in connection with the mosque bombing.
The oil-rich kingdom offered rewards of between one million riyals ($276,000) and seven million riyals ($1.87 million) to anyone who helps in the arrest of the suspects.