Two pairs of robbers who tried to hold up banks in Attica yesterday were thwarted by members of the police’s new motorcycle-bound anti-crime unit Dias. The first attempted raid was on a branch of Alpha Bank in Nea Erythraia, north of Athens. A Greek national entered the bank at 10.30 a.m. and set a package on a cashier’s counter, saying it was a bomb. Pressing a hidden alarm button, the bank manager told the robber that the safe had a time-delay lock and would open in a few minutes. The police arrived and arrested the second suspect, an Albanian, who had been on guard. The Greek suspect gave himself up. Another pair of robbers, both Kazakhs, were also arrested as they fled a failed raid on a branch of Emporiki Bank in Alimos, south of Athens. After trying in vain to smash the bank’s facade with a sledgehammer, they fled in a stolen taxi which was stopped by police.