A knife-wielding man robbing an Islandia gas station got a big surprise when three Good Samaritans stopped him from getting away, Suffolk police said Thursday.

Investigators said three men pumping gas Wednesday night at the Exxon station on Veterans Memorial Highway spotted Roger Elliott, 44, of Hauppauge, holding up the attendant inside. According to police, the men were able to detain Elliot until the authorities arrived. A Fourth Precinct police officer made it to the scene one minute after 911 was called and arrested Elliott.

Elliott is charged with first-degree robbery.