All robberies were committed during his lunch breaks at banks within walking distance of the UN headquarters.
A United Nations headquarters employee was arrested on Monday for robbing four banks over a two-month span, The New York Post reports.
Nigerian national Abdullahi Shuaibu, 53, was charged with two counts of robbery and two counts of attempted robbery.
All robberies were committed during his lunch breaks at banks within walking distance of the UN headquarters.
Mr. Shuaibu committed the first robbery on February 27 when he walked into a Santander Bank and demanded that the teller hand him cash, threatening to shoot if the employee did not comply.
In March, he tried but failed to rob a Bank of America. Later that month, he successfully robbed a separate Santander Bank location.
On Monday, Mr. Shuaibu walked into an HSBC bank and passed a note demanding cash to the teller, who did not read the note and asked for identification. He then told the teller he had a gun and gestured to his hand in his jacket pocket.
After returning to work that afternoon, police arrested Mr. Shuaibu. A retired police officer working at the UN recognized the robber from a surveillance photo previously released by the New York Police Department and led the authorities to his arrest.