SEASIDE PARK, N.J. (AP) _ A quiet dinner at a seaside restaurant was shattered by a propane tank explosion that unleashed an ''umbrella of flames,'' forcing patrons to jump through picture windows and injuring 42, officials and witnesses said.

About 75 people were in the Bayview Restaurant when the tank, used to heat food on a buffet table, blew up Tuesday night, said police Chief Erman Conselice.

''A column of flames shot up,'' said patron Eric Schwartz of Delhi, N.Y. ''Everybody kind of gravitated to the opposite end of the room on the bayview side of the restaurant. There were just plate glass windows with no way of opening or closing them.''

Schwartz said he and others were pressed against the windows.

''Finally, at one point, we started breaking the windows. I picked up a chair and broke a window so that I could get my (family) out of the building,'' Schwartz said.

''It was a nightmare. The flames were shooting out of the buffet table and made a fountain to the ceiling,'' he said. ''It was like there was an umbrella of flames over the buffet table.''

The fire was reported to authorities at 7:09 p.m. and was under control within 90 minutes, officials said.

Schwartz, who said he led family members including his wife and three children out of the restaurant, injured his back and one of his children and his nephew suffered minor injuries.

Thirty of the injured were treated at Community Memorial Hospital in Toms River, where Dr. John Arias said they described how ''everybody went straight out to daylight'' through windows when they could not reach exits.

''They were pretty shaken up,'' Arias said, adding that those treated ranged from children to at least one person above 70.

''All of them are relatively minor injuries,'' including cuts and bruises, he said. ''I haven't seen any burns. Most of the injuries were caused by people getting out of the restaurant.''

Seaside Park Fire Chief Guy Mueller said, ''When we arrived at the scene, all the windows were blown out and the building was totally involved.''

Restaurant owner Angelo Demitry said he was glad his customers and family members escaped with minor injuries.

''This you can replace,'' he said of the building that was turned into a pile of rubble except for the kitchen, which was made of cinderblock. ''You can always start again.''