HOUSTON, Texas (KTRK) — As trick or treaters prepared to hit the streets of Texas City on Halloween of 1987, an accident occurred at the Marathon Petroleum plant sending a cloud of hydrofluoric acid streaming over the city.

More than 3000 people across 50 city blocks were evacuated. More than 800 people went to the hospital suffering from respiratory problems.

At 5:20 p.m. a crane to lifting a 40-ton heater convection unit dropped it on a tank, severing a 3-inch pipe connected to an acid tank.

Hydrogen fluoride gas spewed from the rupture and formed a cloud over the city.

Marathon workers eventually drained the tank of acid.

More than 30 people were admitted into the hospital with hundreds more treated for respiratory problems and eye irritation.

*Original article titled, ABC13’s VAULT: Acid leak over Texas City sends 800 to the hospital in 1987, online at https://abc13.com/abc13s-vault-1987-texas-city-acid-leak/5659492/