Updated

An Athens prosecutor has ordered an investigation into whether police used undue force in the arrest of four suspected bank robbers, three of whom are also suspected of being members of a domestic terrorist organization.

The prosecutor ordered the investigation Monday after the relatives of those arrested accused authorities of torture.

The four men, aged 20 to 24, were arrested Friday in northern Greece shortly after a bank robbery. Police released mug shots seeking further information on them from the public. All four photos appeared to have been digitally altered, with signs of bruising showing through the alteration on the left side of three suspects' faces.

Police say the suspects were armed with assault rifles and were arrested during an "operation."