Loyalist troops in Burundi have arrested at least three leaders of a failed coup against President Pierre Nkurunziza, a presidential spokesman said.

Gervais Abayeho said those arrested on Friday were two army generals, including former Defence Minister Cyrille Ndayirukiye, and a police general.

Major-General Godefroid Niyombare, who led the coup attempt, was "still on the run, his whereabouts are not known to us", Abehayo told the Reuters news agency.

The arrests came as Nkurunziza returned to the capital Bujumbura days after the attempted coup, officials in the president's office said, adding that he was due to address the nation on Friday, 

"He is in Bujumbura in a very secure place," an aide to the president told the AFP news agency. "He will address the nation today."

But Burundians say they want proof that Nkurunziza is in the country, whose borders and the airport in Bujumbura had been declared closed by army officers who attempted to stage the coup.

"People say they want to hear the declaration of the president on radio or national television, in order to be sure that he is here in Burundi," Celestine Sadiki, an NGO worker in Bujumbura, told Al Jazeera. 

More than 50,000 Burundians have fled the violence to neighbouring nations in recent weeks [Reuters]

The coup leader's spokesman, Venon Ndabaneze, confirmed to the AFP news agency by phone that organisers of the coup had decided to surrender when loyalist troops arrested him, together with deputy coup leader Cyrille Ndayirukiye and another senior figure among the mutineers.

"We decided to give ourselves up. We have laid down our arms. We have called the security ministry to tell them we no longer have any arms," Ndabaneze said, seconds before he could be heard being arrested.

The AFP said it remained on the line as the leaders were detained.

The dramatic end to the coup attempt came shortly after the presidency announced that Nkurunziza - who was in neighbouring Tanzania when the coup was declared - had returned to the country.

Nkurunziza, 51, had travelled to Tanzania for talks with leaders of the five-nation East African Community to try to resolve the political crisis in Burundi, triggered by a decision by his ruling CNDD-FDD to declare him candidate for the June 26 elections.

The decision has led to violent protests, with the president's critics saying it contravenes the constitution, which allows presidents to run for only two five-year terms, and goes against a 2006 peace deal that ended a 13-year civil war in the land-locked central African nation.

Supporters of Nkurunziza say the president is eligible for a third term, arguing that when he was installed in 2005 by an act of parliament he was not directly elected by people.

More than 50,000 Burundians have fled the violence to neighbouring nations in recent weeks, with the UN preparing for thousands more refugees.

In his message announcing the coup, Niyombare signalled he did not want to take power himself, vowing instead to work for "the resumption of the electoral process in a peaceful and fair environment".

Niyombare is a highly respected figure who was sacked from his intelligence post in February after he opposed Nkurunziza's attempt to prolong his 10-year rule.

Source: Al Jazeera and agencies