At least 36 people were injured when suspected Maoist rebels exploded a powerful bomb at a government office complex in the heart of Nepalese capital Kathmandu Tuesday.

A dozen labourers working inside the office-cum shopping complex, which is in the final stages of construction, and two dozen pedestrians standing near the micro-bus stand were injured in the incident, said the police.

The injured have been admitted to nearby Bir Hospital for treatment. Security personnel surrounded the complex after the blast, which comes just before the Hindu festival of Diwali.

The Rs 22 crore, 36,000 sq metre seven storey complex is the largest ever being built in Kathmandu. Both the escalators as well as the front façade of the building were damaged, and broken window-panes were seen scattered 200 metres from the building on the main road. The damage is estimated at over Rs two crores.

The police said three unidentified people, one of them carrying a bag, entered the -storey commercial complex of the Employees' Provident Fund in Sundhara at 2.30 pm (local time).

After overpowering the lone guard at the gate, they planted the bomb inside the complex and escaped. They also warned the guard to escape before leaving.

"They overpowered me and forcibly entered the building when I stopped them to check their bag, and minutes after they returned after planting the bomb on the first floor, a huge explosion was heard", said the guard Kulman Lama.

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