The mayor of Philadelphia is urging a judge not to impose a prison sentence on the owner of a nightclub whose business collapsed collapsed seven years ago on a river pier, drowning three young women and injuring dozens of others.

Mayor John F. Street sent the three-sentence letter of support this week on behalf of Michael Asbell, a real estate developer who was to be sentenced Friday.

Asbell, 65, and the club's operator, Eli Karetny, 66, face maximum terms of 2 1/2 years to five years for each of three involuntary manslaughter charges. Asbell has pleaded no contest, and Karetny pleaded guilty.

The mayor's letter of support is included in court papers filed by Asbell's attorneys.

"There is no question in my mind that his incarceration would serve neither his best interests nor the interests of the general public," Street wrote. He called Asbell "an important civic leader" who has been "committed to his city."

The Heat nightclub collapsed into the Delaware River in May 2000.

Their lawyers portrayed the men as community-oriented businessmen who never would have risked lives by opening the club that night had they had known it could have collapsed.

Prosecutors said the men had been warned repeatedly, including on the day of the disaster, that it was dangerous.

Families of the three victims were awarded $7.4 million each in civil damages from Asbell, Karetny, the city and others.