Nassau County police are investigating whether three Friday night gunpoint robberies of retail stores are related.
The robberies -- by either one or two masked men -- occurred within two hours.
The suspect went behind the register, pointed a handgun at the 32-year-old female clerk and grabbed an undisclosed amount of cash.
There were two customers and three employees in the store at the time. No injuries were reported, police said.
At 8:30 p.m., a 21-year-old male employee at the Auto Zone on Burnside Avenue in North Lawrence was approached by a robber who demanded cash from the registers.
Police said the robber fired a shot before fleeing the store with the money. There were two employees and a customer in the store, but no one was injured.
The last robbery was reported at 8:50 p.m. at the Family Dollar on Nassau Road in Uniondale, where two men -- one pointing a gun -- grabbed cash from a 35-year-old female employee, police said.
Detectives ask anyone with information about these crimes to contact Nassau County Crime Stoppers at 800-244-TIPS. All callers will remain anonymous.