FAIRBANKS -- A Fairbanks man may have been stabbed because he refused to buy alcohol for a teenager.

A criminal complaint says 18-year-old Benjamin G.I. Tumbloo of Fairbanks approached the 49-year-old man in downtown Fairbanks on Wednesday and asked him to buy alcohol, but the man refused.

The Fairbanks Daily News-Miner says when the two encountered each other later, Tumbloo stabbing the man and rode away on a bicycle, according to police.

Tumbloo told police he stabbed the older man in self-defense because he pulled a knife on him. But witnesses told police they did not see that happen. The victim underwent surgery for a stab wound to his liver.

Tumbloo was arraigned Thursday. No bail was granted given the severity of the crime and the strength of the evidence.