PALO ALTO (CBS SF) — An alert witness helped Palo Alto police arrest three suspects responsible for an armed robbery at an Arco gas station on Sunday evening.

Around 8:40 p.m., police dispatchers were first notified of the robbery at 699 San Antonio Road. A preliminary investigation showed that a male suspect entered the store, pointed a handgun at the cashier and demanded money, police said.

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The cashier, a man in his 40s, obliged and opened the register for the robber out of fear for his life, police said. The cashier was not injured and the amount of money stolen was not disclosed.

The suspect ran out of the store and fled in a vehicle with two other suspects. The cashier then told a witness, who just entered the store as the robbery was taking place, what had transpired, and the witness quickly left the store to see where the suspects were fleeing.

The witness, a woman, saw a vehicle matching the cashier’s description and called 911. The woman followed the vehicle while still on the phone with dispatchers, notifying them of the vehicle’s location.

Responding officers were able to locate the vehicle and stop the suspects on Alma Street near Palo Alto Avenue. All three were arrested without incident.

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(Left to right) Lopez, Solis and Benitozavala (Photo: Palo Alto PD)

Police found the stolen cash along with drugs and drug paraphernalia in one suspect’s bag. An unsecured, loaded handgun, which was reported stolen out of Salinas, was also found. An elementary school-aged child was also in the vehicle, and the firearm was within arms reach of that child, police said. A teenage juvenile was also in the vehicle.

The child was released to relatives and the teenager was taken to a youth shelter with the help of the Santa Clara County Department of Family and Children Services.

Jesus Benitozavala, 28, Yesenia Florez Lopez, 26, and Jose Solis, 19, were booked into Santa Clara County Main Jail. They each face charges of robbery, conspiracy to commit a crime and child endangerment.

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Benitozavala, the getaway driver, and Solis, the gunman in the robber, also face charges of a stolen firearm. Lopez faces drug possession charges.