Siliguri/Kolkata, May 13 (IANS): Over 50 people, including at least 20 school children, were injured in northern West Bengal, as tremors were felt in most parts of the state including capital Kolkata on Tuesday, officials said.

However, there were no reports of any death so far, said state home secretary Basudeb Bandopadhyay. Chief Minister Mamata Banerjee appealed to people to remain calm.

In Kolkata, Metro train services were halted due to the tremors, which were also felt in Murshidabad, Durgapur, Siliguri and other places.

With the after-effects of the April 25 quake in Nepal and also large parts of India still very fresh in their memory, people rushed out of offices, shopping malls, commercial establishments and homes, while trains were stopped on their tracks in various areas. Some patients even ran out of hospitals.

Four tremors were experienced in the seven north Bengal districts starting from 12.35 p.m., with the last felt about one and a half hour later, Met department sources said.

The quake at 12.35 p.m. measured 7.3 on the Richter scale.

The second tremor (5.4) occurred at 1.04 p.m., while the two other were felt at 1.07 p.m. (6.2) and 2.04 p.m. (4.2).

The injuries were caused due to fall, slipping from the stairs of high-rise buildings, and stampedes as panicky people rushed for the open skies.

"Over 30 people were injured in the Siliguri sub-division," said an official.

Fifteen people were treated at the Siliguri district hospital.

Two injured victims were admitted to the North Bengal Medical College and Hospital, while 10-12 others were treated and allowed to go, said hospital superintendent Sabyasachi Das.

About 20-25 school children were injured in various places as they rushed out of their classrooms after the tremors began.

"Some of them fell from the stairs. Some fell in the classroom or corridor and injured themselves," said an official.

In North Bengal University, examination was held under the open skies as the authorities did not want to take any risk by holding the tests in the classrooms.

In various areas of north Bengal, train movement was halted on the tracks. Even the Rajdhani Express from Guwahati was stopped for some time.

Across the state, a large number of buildings developed cracks.

"Services were temporarily suspended. All the commercial trains were controlled at different stations between 12.48 p.m. and 1.15 p.m.," said a Kolkata Metro Railway release.

Cell phone services were disrupted in several stretches.

Mamata Banerjee assured all support from her government.

"Earthquake has once again struck many parts of our state and other parts of the country and abroad. I appeal to our people to maintain calm. Our government will provide all support," she posted on Facebook.

She said a round-the-clock control room has been opened at Nabanna. The numbers were 1070 and 22143526.