Kansas City police were involved in a standoff at an apartment complex Tuesday afternoon, where several people were possibly being held against their will, according to police.

Officers responded to a 911 call around 1 p.m. in the 1300 block of Highland Avenue, near Rockhurst University. The caller reported that someone was holding several people in an apartment against their will, according to Officer Phil DiMartino, a KCPD spokesperson.

Officers tried to negotiate with a suspect inside the apartment before calling an Operation 100 — a police standoff that includes trained negotiators and extra police units.

As negotiations continued, multiple people exited the apartment building around 3 p.m., DiMartino said. Another person left the building at 4 p.m., leaving the suspect alone in the apartment, DiMartino said.

After further negotiations, the suspect left the apartment and was taken into police custody around 8:30 p.m.. No one was injured in the standoff, DiMartino said.

Kansas City police officers are investigating what led up to the situation, according to DiMartino.