Hyderabad, June 30 : Six workers were feared killed and 20 others injured in a massive reactor blast at an industrial unit at Pashamailaram near Hyderabad on Monday.

The incident occurred at a chemical factory in the industrial area in Sangareddy district around 9 a.m.

The explosion triggered a huge fire, which engulfed the premises of Sigachi Chemicals. Firefighters rushed to the spot to douse the fire. Eleven fire engines were pressed into service to control the fire.

Police, fire services and other personnel launched rescue and relief operations. Ambulances were also seen at the spot to shift the injured to hospitals.

The injured were admitted to government and private hospitals. The condition of some of the injured is stated to be critical.

Six of the workers were feared killed on the spot while an injured worker reportedly succumbed at a hospital. Officials have not yet confirmed deaths.

According to eye-witnesses, such was the impact of the explosion that workers were tossed in the air and fell several meters away. The manufacturing unit in the factory collapsed under the impact of the blast, while fire spread to the adjoining building within the factory premises.

Several workers were working near the reactor when it exploded. Migrant workers from Odisha, Uttar Pradesh and other states were employed in the industrial unit.

The explosion and fire sent panic among the employees in the chemical unit and the adjoining factories. They ran out of the premises.

The rescue workers were also using earthmovers to remove the debris of the demolished structure, as there are apprehensions that some workers may be trapped under it.

Sangareddy District Collector P. Pravinya and Superintendent of Police Paritosh Pankaj also rushed to the spot and were supervising rescue and relief operations.

Personnel from various industrial units and staff of different departments also joined the rescue operation.

More details were awaited as operations continued.

/IANS