RENTON, Wash. -- A 73-year-old man was stabbed at the Renton Transit Center after 6 p.m. Thursday.

Renton Police Detectives said the incident started at a fast-food restaurant earlier in the day, when a juvenile was robbed of his cell phone by several people. The teen went home and told his father and grandfather about the incident.

The three went to the transit center and confronted the people who stole the phone. A fight between the two groups occurred and the grandfather was stabbed. Police said he was taken to Harborview and is now listed in stable condition.

Three people were arrested at the scene, but police are still investigating their exact involvement.

An additional stabbing victim went to the hospital later in the night and admitted that he was involved in the fight at the transit center.

Police believe more than one person, possibly including the 73-year-old man, was armed with a knife when the incident occurred.

The second victim's injuries were not life threatening.

Renton police are interviewing eye witnesses and reviewing the video tape from the city's security system in the transit center.

Police say if you have any information, call Sergeant Tracy Merrill at 425-430-7527.