He said the gunmen first let three hostages go and then negotiated with police before the last two were freed.
They eventually turned over their guns and a grenade before police arrested them, Manuitt said.
The four men, all in their 20s, had threatened to kill hostages if security forces stormed the bank or tried to storm the getaway vehicle.
The standoff began after the men, reportedly armed with grenades and rifles, walked into the bank and demanded money.
However, they were interrupted by an off-duty police officer who went to use a cash machine in the bank, AP reported.
At least 30 hostages, including several children and a pregnant woman, were detained, many of whom could be seen pleading for food and water through the bank's windows during the incident.
"We are in real danger. They can kill us. Please help," read a placard placed at one of the branch's windows.
Hundreds of police were deployed during the standoff and helicopters flew over the branch of Banco Provincial, owned by Spain's BBVA.
"After five or six hours, they began to let down their guard saying, 'You
aren't going to die'," freed hostage Juan Carlos Gil told AP.
"They were nervous, but it was all an atmosphere as if they were everyone's friends."
Seven captives made it out of the bank during the standoff there, including several who were released and two who fled.