Ahmad, a 1978-batch IPS officer, will, however, have a short tenure as he is set to retire in February.
On taking charge as the new DGP, Ahmad said the state police was capable of dealing with all the challenges.
"I will do everything to boost the morale of police, which is capable of dealing with all situations," he said.
Three other IPS officers -- Himmat Singh, D D Mishra and R K Rai -- also retired.