Tension gripped Kerala as an unidentified person allegedly hurled an explosive substance at the state headquarters of the ruling CPI(M) Thursday night.
Police said the explosive substance was hurled at the AKG Centre, situated in the heart of the capital city, by a motorbike-borne man at around 11.30 pm.
CPI(M) leaders who reached the spot alleged that it was a "bomb attack". Some party leaders, who were staying at the AKG Centre, said they heard a powerful blast outside the building.
Police were alerted immediately and a team of top officials inspected the spot and CCTV cameras were scrutinised. A bomb squad also inspected the spot.
Senior CPI(M) leader and LDF convener E P Jayarajan, who stays in the neighbourhood, alleged that the Congress was behind the provocative action and appealed to the CPI(M) workers to remain calm.
The opposition Congress on Friday categorically rejected the Marxist party's charge that they were behind the incident and said attacking the political opponent's office was not their party's policy.
In his reaction, Leader of Opposition in the state Assembly, V D Satheesan said the party leadership had no knowledge of the midnight incident and would let the police investigate and ascertain the truth.
Alleging that the people of the state clearly know that the Congress party and its workers were the ones who plan and execute such attacks, he asked the ruling party to explain on what grounds they were levelling charges against them.
"The CCTV visuals were not clear... Let the police probe and find out the real culprits.. The Left government is facing a series of allegations and they are on the defense due to our ongoing protests. Those who want to shift the attention and focus from the present issues are the ones behind the attack," he told reporters.
Asked whether he was suspecting that CPI (M) itself was behind the attack, Satheesan did not give a clear reply.
"It is an important day for us due to Rahul Gandhi's Kerala visit. Do you think we would attack the AKG Centre and shift the focus from the present issues being faced by the government?" the Leader of Opposition asked.
KPCC chief K Sudhakaran also rejected the Marxist party's allegation and accused LDF Convener E P Jayarajan of 'masterminding' the attack against the party headquarters.
Meanwhile, security has been beefed up at the party offices of the Congress and CPI(M) in various places in the wake of the incident. Many Kerala ministers, including Finance Minister K N Balagopal, Education Minister V Sivankutty, rushed to the spot.
Several workers of the CPI(M) took out a protest march in the city. The workers also protested in Pathanamthitta and other places in the state.
As tense situation prevailed, the police tightened security around offices of the Congress in the state.
CPI(M) state secretary Kodiyeri Balakrishnan called for a peaceful protest.
Accusing the Congress-led UDF of deliberately creating provocation, Balakrishnan urged the party workers not to fall in their trap.
An investigation has been launched to identify the culprits behind the attack, police said.
The incident comes ahead of Congress MP Rahul Gandhi's visit to his constituency Wayanad on Friday.
(Wiyth PTI Inputs)