Patna, May 14 (IANS) Nearly twenty-four hours after the killing of a senior journalist of Hindi daily Hindustan in Bihar's Siwan district, police are yet to make any breakthrough even as opposition NDA leaders have termed the incident as "return of jungle raj" in the state.

Meanwhile, the last rites of Rajdeo Ranjan, who was shot dead at a busy market near the Station Road on Friday night, were held in Siwan.

Media persons, wearing black badges, also held a protest in the district and demanded arrest of those responsible for the crime. Journalists in Patna also took out a protest march and demanded justice to Rajdeo's family.

Siwan Superintendent of Police Saurav Kumar Sah said that initially four suspects had been detained in connection with the killing of Ranjan, the Siwan bureau chief of the Hindi newspaper, which is part of the HT Media, but later, two were released following questioning.

"Only two people have been arrested and interrogated in connection with the killing," he said.

However,a senior police official at police headquarters here told IANS that no major breakthrough in this case has been made so far.

"A manhunt has been launched to arrest the killers soon," the official said.

The Bihar Police headquarters sent a Special Task Force (STF) and Special Operations Group to Siwan late Friday night.

"We will nab the people behind the killing and will not spare any one," said Bihar Police chief P.K. Thakur.

It was a sheer coincidence that Ranjan, 46, was planning to celebrate 18th marriage anniversary on Saturday (May 14) but it never happened.

His family said he had no enmity with anyone and was busy preparing for the last few days to celebrate his anniversary.

Coming close on the heels of the killing of teenager Aditya Sachdeva allegedly by the son of a ruling Janata Dal-United lawmaker in Gaya district, the journalist's murder has been described by opposition Bharatiya Janata Party (BJP) as another addition to the "fast-mounting proof of the return of jungle raj in Bihar".

Chief Minister Nitish Kumar and Rashtriya Janata Dal chief Lalu Prasad have condemned the killing and directed top police officers to take prompt action in nabbing the culprits.