New Delhi, India (CNN) -- At least 98 people fell ill Wednesday as chlorine gas leaked from a large, corroded canister at a port facility in Mumbai, emergency officials said.
The gas wafted through a college building in the vicinity around 3:30 a.m., according to authorities.
Uday Tatkare, Mumbai's chief fire officer, told CNN that about 84 people have been hospitalized, most of them students and port workers. Others were discharged after being treated.
India's shipping ministry said only 59 people had been hospitalized, but said seven of those patients were under intensive care in stable condition.
The exposure mainly caused breathing problems, Tatkare said.
The Indian shipping ministry is demanding a report on the incident from the Mumbai Port Trust, which owns the hazardous goods storage facility from which the gas escaped. The ministry said records from the port trust showed the gas tanks as empty.
Fire crews threw a water blanket at the site to contain the leak, Tatkare explained.
At least four fire officials also suffered exposure and have been admitted to a hospital, he added.
Authorities have evacuated a residential neighborhood close to the scene, but some passers-by did come in contact with the gas, the chief fire officer explained.
"The situation is now under control," Tatkare said.
Experts are neutralizing more than 100 other chlorine canisters that officials say have been lying in the same compound since 1997.
In a statement, the Mumbai Port Trust claimed that importers had not taken delivery of the gas tanks from its facility, about 8 km (4.9 miles) from the docks, for all these years. It said it was investigating the situation.