Indian Home Minister Palaniappan Chidambaram (courtesy Creative Commons)

At least 61 people were injured, according to the BBC.

Indian officials are investigating Huji, a group linked to al-Qaeda, that took responsibility for the bombing in an email, according to The Daily Beast.

The email demands that a man sentenced to death 10 years ago for involvement in an attack on the Indian parliament not be hanged, the BBC reports.

The bomb was near the first security checkpoint at the court. Many were gathered there for entry passes, officials told Bloomberg.

The bomb left a crater on the road and shook the courthouse, BBC reports. Many judges and lawyers fled the courthouse.

Indian Home Minister Palaniappan Chidambaram has urged the country to stay calm and united.

“I appeal to the house and the people of the country that we must remain resolute and united,” Chidambaram told lawmakers, according to Bloomberg. “We should never be intimidated by terrorist groups, we are determined to track down the perpetrators of this horrific crime and bring them to justice.”

The attack occurred despite a high alert across the city. The incident has renewed doubts about India’s ability to protect important institutions, the BBC reports.

Three months ago, another attack was carried out against the same building. No one was hurt during that attack where a bomb exploded in a car.

Bombings in India also took place in July when three bombs in Mumbai killed 26. No groups have taken responsibility for the attacks.

Other bombings occurred in February where 16 people were killed in Pune and in December where one girl was killed and 34 were injured in Varanasi.

Since November 2008, India has suffered six terrorist attacks.

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