UPLAND (CBSLA.com) — Crews were on the scene of a barricade situation on Saturday that was prompted by four teenage suspects who allegedly robbed a medical marijuana center.

According to the Upland Police Department, officers were sent to the 700 block of North Mountain Avenue for report of a robbery at a medical marijuana center.

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A preliminary investigation revealed three employees were approached by four armed suspects in the parking lot as they were leaving.

Authorities explained one employee was pistol whipped, and another was shot in the leg. The suspects allegedly zip tied all three victims, and stole money before leaving the location in one of the employee’s Lexus.

According to police, the suspects stole an undisclosed amount of cash and marijuana.

The victim’s conditions remain unknown at this time.

Police went on to explain three of the teenagers traveled to an apartment complex, located in the 1300 block of Randy Street, and barricaded themselves inside of a residence for more than six hours.

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The barricade situation safely ended around 11:00 a.m., officers said.

A neighbor who wished to remain anonymous, shared with CBS2’s Greg Mills that she feared for her life during the standoff.

Diego Sanchez, 19, and two teenagers under the age of 18-years-old, were peacefully detained.

The fourth suspect, a 30-year-old man, was found in a separate apartment, and was also taken into custody by officers on scene.

All four suspects are being held on charges for robbery, assault with a deadly weapon, and kidnapping.

In total, five guns were recovered at the scene, authorities explained.

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Mills reported the medical marijuana dispensary has been indefinitely closed as zoning regulations do not permit the operation of dispensaries in Upland.