He was later nabbed and was being questioned, they said.
One Ashok Reddy, who seemed to be under "mental depression", after scaling the gate No.1 of the Assembly building in the morning hours entered the premises and broke the main door of the building and sat inside the meeting hall, a senior police official said.
"The staff alerted the police after noticing Ashok Reddy sitting inside and verifying the CCTV footage, he has been taken into custody," Deputy Commissioner of Police (Central Zone) V B Kamalasan Reddy said.
According to his family members, he had left his house at 5 AM today, the police officer said.
"He seems to be under mental depression and was behaving abnormally for the past few months and last evening he was also taken to a hospital," he said.
A case has been registered against Ashok Reddy in connection with the incident and he is being questioned, police said.
Necessary action will be taken against those responsible for the security lapse after further investigations.
