Chechen authorities have arrested suspects in connection with Thursday's car bomb attack on President Aslan Maskhadov, the breakaway Russian region's chief prosecutor told Reuters on Friday.

Khavash Sirbiyev did not say how many people had been arrested or who they were but said the investigation was continuing. Weapons and ammunition had been found in a building near the scene of the attack, he added, without elaborating.Chechnya's former leader, Zelimkhan Yandarbiyev, was questioned by a court on Friday but absolved of blame in the attack, Mask-ha-dov's spokesman Mayerbek Vachagayev said.

But two leaders of maverick Islamist paramilitary groups who were also summoned to the court failed to appear, he added.

Maskhadov disbanded the Islamic paramilitary units last weekend after they clashed with his troops on July 15 at the town of Gudermes, leaving nine dead. Chechen officials have linked Yandarbiyev to the disbanded units.

Yandarbiyev left the courtroom insisting he was prepared to swear on the Koran he was not involved in the bombing, Interfax news agency reported. The court did not ask him to swear.

"I am 1,000 times certain that it was the work of Russian special forces, making use of the Gudermes events to complicate the situation within Chechnya and increase tensions," he said.

Sirbiyev had previously accused Yandarbiyev of seeking support from the Islamist units, but Yandarbiyev on Friday told Interfax such accusations were "a stupid mistake."