Patna, Nov. 15: The crime graph continued to soar in the Bihar capital as a college professor and a trader were shot dead today.

The double murder came on a day when talks between the Indian Medical Association (IMA) and the Rabri Devi government failed to end the doctors? strike, called to protest the murder of a surgeon on Diwali.

Brahmadev Prasad Akela, a professor at Darbhanga?s CM College, was killed when he resisted a gang of robbers in Patna. Tarun Kumar, a trader, was gunned down by two men when he was opening his shop.

While the doctors reiterated their earlier demands ? arrest the killers of N.K. Agrawal and ensure the safe return of Nagendra Prasad, a fellow practitioner ? junior doctors of Patna Medical College and Hospital are on the verge of joining the indefinite strike.

The Patna branch of the Indian Dental Association as well as traders and businessmen of the city are already on strike and the Bihar Medical Officers? Association has threatened to go on mass leave after three days.

Following reports of Agrawal?s family members receiving more ransom calls, many doctors have decided to leave the state.

?A murder does not rule out payment of ransom. Murder itself has cost us quite a lot,? an anonymous caller reportedly told a relative of Agrawal. An unconfirmed report said the slain doctor?s relatives have received at least 12 such calls in the past three days.

Agrawal and his assistant Arvind Kumar were shot dead inside their clinic at Kadamkuan on Friday evening, allegedly for their failure to pay extortion money.

City-based heart specialist A.K. Thakur and orthopaedic surgeon R.N. Singh are among those who have been allegedly targeted after Friday?s incident. The two have received ransom calls at their clinics in the past couple of days. According to reports, 22 doctors are on the list of criminals.

Director-general of police Narayan Mishra, who met the bereaved family of Agrawal yesterday, promised to take stringent action against criminals. ?I want to tell the doctors that we are at their service and will do whatever is necessary to ensure their security,? he said. A task force is looking into the case, he added.