The city prosecutor’s office has decided not to press charges against a 28-year-old man in connection with a fight on Memorial Day at Heeia Kea Pier that ended in the death of a 26-year-old Kaneohe man.

Nelden Torres died Monday at a hospital where he had been taken in critical condition after the fight.

The city Medical Examiner’s Office said Torres died of bleeding in the brain due to blunt force trauma, and determined the manner as homicide. Torres had alcohol and cocaine in his system, office said.

Police had responded to a fight 6 p.m. May 30 and found Torres unconscious with head injuries near the boat launch area.

The 28-year-old man was arrested Thursday on suspicion of first-degree assault after a CrimeStoppers request seeking witnesses and information concerning the fight.

However, the city prosecutor decided not to press charges since witnesses told police that Torres sought out the suspect at the Kaneohe pier. The suspect apparently was acting in self-defense, a spokesman for the prosecutor said.

The victim apparently threw the first punch and was injured when he fell and hit his head on the asphalt, the spokesman said.

There have been calls to prohibit drinking at the sandbar, require permits for concerts, ban concerts and make it a bird sanctuary because of problems caused by the large crowds on holidays.

At low tide about three acres of sand at Ahu o Laka are exposed. Heeia Kea Pier is the nearest access point to the midbay sandbar.

During the Memorial Day weekend, Heeia Kea Pier was busy with people loading and unloading boats for trips to the sandbar.

The state Department of Land and Natural Resources estimates that there were more than 200 boats and 500 people on the sandbar during the holiday.

Seven department conservation officers patrolled the sandbar and harbor area but had already left when the fight occurred.

Three were assigned to Heeia Pier, and four were on two patrol boats at Ahu o Laka or in the bay, department spokeswoman Deborah Ward said.

In 2007 three men were treated for injuries they sustained on the sandbar after a fight broke out on Labor Day, and the state stepped up patrols in Kaneohe Bay on holiday weekends.