A botched robbery at a San Francisco medical marijuana dispensary triggered a tense overnight SWAT standoff Tuesday in the city’s Bayview District that lasted over seven hours before the suspect was taken into custody, according to San Francisco police.

Police said three suspects were already in custody in connection with the robbery. An additional suspect was believed to have barricaded himself inside the building near Jennings Street and Wallace Avenue at around 3:50 a.m.

“Officers from the Bayview police station responded to a robbery in progress at a business located in the 2100 block of Jennings,” San Francisco police Sgt. Michael Andraychak. ”Upon arrival, three suspects wearing ski masks fled from the front of the building. A brief foot chase ensued and those three suspects were taken into custody without incident. “

“We believe there is a suspect inside and possibly employees (of the pot club),” Andraychak added. “We are trying to establish contact with those inside.”

The neighborhood was quickly cordoned off and SWAT officers took up positions surrounding the structure.

Andraychak said concern was high because the employees inside the building had not responded to police demands to leave the building.

The standoff continued at 7:45 a.m., but others had been detained and investigators were trying to determine if they played a role in the robbery or just happened to in the area.

“People were observed sleeping in a car parked nearby,” Andraychak said. “Those individuals have been taken to the Bayview station to be questioned.”

Just before 10:30 a.m., the suspect was in police custody. It was still unclear immediately after the arrest whether or not the one suspect had hostages inside the pot dispensary.