Kerala's coastal Alappuzha district was rocked by back-to-back killings of two party leaders, the first belonging to the SDPI and the second to the BJP, leading to clamping of prohibitory orders by police on Sunday.

Following the killing of an SDPI state secretary, a BJP leader was hacked to death subsequently in 12 hours and prohibitory order under CrPC Section 144 was imposed in the entire Alappuzha district on Sunday, district officials said.

Kerala Chief Minister Pinarayi Vijayan Sunday condemned the killings and said steps will be taken by the police to nab the culprits and those behind them.

The Chief Minister said such heinous and inhumane acts of violence were dangerous to the country and that people should keep away from such groups and their hateful activities.

K S Shan, the state secretary of the Social Democratic Party of India (SDPI) in Kerala, was brutally attacked on Saturday night while he was on his way back home and his party alleged the RSS was behind it.

Shan succumbed to his injuries at a Kochi hospital around midnight, police said.

Hours later, BJP's OBC Morcha state secretary Ranjeet Sreenivas was hacked to death by some assailants who barged into his house on Sunday morning, police said.

Police said it suspects the fatal attack on Sreenivas, also a member of the BJP state committee, was in retaliation to the killing of Shan.

State Police Chief (SPC) Anil Kant, told the media, that senior police officers were camping in the district and additional forces have been deployed there.

He said that ADGP-Law and Order would be heading the probe into the two killings and that the police would soon be rounding up troublemakers, 'goondas' and their leaders in the area to prevent another such incident from happening in the near future.

Kant also said a state-wide alert has been announced and all District Police Chiefs have been directed to closely monitor the law and order situation there and if required, prohibitory orders would be imposed and additional forces would be deployed.

Terming the BJP's leader's killing as disgraceful, Union Minister of State for External Affairs and Parliamentary Affairs V Muraleedharan, told reporters here, that had the police taken appropriate steps after the murder of the SDPI leader, the situation would not have escalated to the present level.

He said Sreenivas' killing was a result of the failure of the state government and the police to take precautionary or preventive steps after the SDPI leader's murder.

He also said that according to information he has received, SDPI was behind the killing of the BJP leader.

Muraleedharan said that such incidents were not new in Kerala and alleged that in a similar incident in Palakkad recently, the government and CPI(M) actively protected the assailants.

He said that the Left government in Kerala was giving a free hand to Islamic terror groups and this was making things worse in the state.

The Union Minister said the Chief Minister should change his administration's stance towards such groups and take strict action against them.

He denied allegations that the RSS was behind the SDPI leader's death, saying in that area the struggle for dominance was between the CPI(M) and SDPI and added that police should investigate who is trying to implicate BJP in the matter.

He said that even if Sreenivas' death was a retaliation, as claimed by some, then the Chief Minister should clarify whether it was an 'eye for an eye' system in the state.

BJP's Kerala unit president K Surendran said efforts were being made on social media to equate the RSS with SDPI, which is allegedly the political outfit of the Islamic organisation Popular Front of India (PFI).

He alleged that even the Chief Minister was supporting the PFI as in many municipal corporations in the state the CPI(M) and SDPI were actively supporting each other.

His reaction appears to be in response to the allegation by Leader of Opposition in the State Assembly V D Satheesan that BJP and SDPI were creating communal disharmony in the state.

He also alleged that both groups were engaging in such activities to create political space for themselves and therefore, the state government and the people of Kerala should stay away from such groups.

Satheesan further alleged that the agenda of these groups was to divide the state along communal lines and that the Left government should take stringent action against them.

He said that if the government was intending to capitalise on the situation for its own benefit then such a move would be obstructed by the Congress-led UDF.

SDPI's Kerala president, meanwhile, issued a statement refuting allegations that it was behind the killing of the BJP leader.

It said that it was not going to take another person's life in retaliation for Shan's death and that it has faith in the rule of law in the country.

SDPI said the motive behind implicating it for Sreenivas' killing was to tarnish its image.

SDPI leader, Shan, was on his way home when a car rammed into his bike and as he fell down, the assailants assaulted him leading to his death, police said.

Following the BJP's leader's killing, prohibitory order was clamped in Alappuzha.