NEW DELHI: Lalit Mohan Jha, a key accused in the Parliament security breach incident, was arrested on Thursday evening, police sources said.

Jha, accompanied by a man, reached the Kartavya Path Police station in the national capital where he was handed over to the Special Cell.

"Lalit Jha came to Kartavya Path Police station where he was arrested. He was handed over to Special Cell which is investigating the incident," an officer said.

In a major security breach on the anniversary of the 2001 Parliament terror attack on Wednesday, two men -- Sagar Sharma and Manoranjan D -- jumped into the Lok Sabha chamber from the public gallery during Zero Hour, released yellow smoke from canisters and shouted slogans before being overpowered by MPs.

Around the same time, two others, including a woman, raised slogans and released yellow smoke from canisters outside the Parliament premises, prompting police to round up the duo.

According to police, the Parliament security breach was well-coordinated, meticulously planned and carried out by six people.

While Sagar, Manoranjan, Amol and Neelam were nabbed from incident spot, their accomplice Vishal, in whose house they stayed before reaching Parliament, was detained from Gurugram.