The New York police department was upside down as it received numerous calls from residents of south Manhattan for unusual odor in different places in the region. Several buildings were evacuated while part of the railway that connects Manhattan to New Jersey had been shut down.

The Homeland Security office reassured the citizens by saying there was no indication for terrorist attack. New York authorities announced that there was no risk for the public health but 19 people went to the hospital with light respiration problems, stomachache and dizziness.

New York’s Mayor Michael Bloomberg held also a news conference to assure residents that the city`s air-quality detectors had found no cause for alarm. He also said that the railway service was back in normal.

Authorities are still investigating the region so as to found out what caused the odor.

According to CNN, last August four people had been carried to the hospital with respiration problems from gas leak in Queens in State Island.