Sri Lanka's government Friday rejected a call by separatist Tamil Tiger rebels to revive a 2002 cease-fire, a week after Colombo officially withdrew from the truce. Keheliya Rambukwella, a minister and the government's defense spokesman, claimed the rebels had used the cease-fire to strengthen themselves militarily and "to continue their terrorist activities." "Considering the ground realities, it (the rebels' offer) looks hilarious," said Rambukwella. His comments come a day after the rebels' political-wing chief B. Nadesan said the Tigers were "ready to implement every clause" of the Norway-brokered truce and respect it "100 percent." "We are shocked and disappointed that the government of Sri Lanka has unilaterally abrogated the cease-fire agreement signed in 2002," Nadesan said in a statement, the first public reaction to the government's decision. Meanwhile, Japanese envoy Yasushi Akashi was scheduled to begin a three-day visit to Sri Lanka on Sunday to discuss the "current situation of the peace process and its future," the Japanese Embassy said in a statement. Japan, a key backer of the Norway-brokered cease-fire, appointed Akashi as its peace envoy. Akashi played a pivotal role in organizing a 2003 donor conference in Tokyo to raise funds to rebuild areas in Sri Lanka destroyed by the war. A new wave of nationwide fighting and attacks has killed at least 207 people - 197 rebels, six soldiers and four civilians - since the government withdrew from the 2002 cease-fire on January 3, according to the military. Sri Lanka's government announced last week it was pulling out of the cease-fire, saying that growing violence in the last two years had rendered it irrelevant. The truce formally becomes invalid on January 16. Despite the cease-fire, near-daily ambushes, assassinations and air strikes have killed more than 5,000 people in the last two years. Fighting continued Friday in the embattled north. Sri Lankan fighter jets destroyed a rebel sea base in the Nayaru area of rebel-controlled Mullaithivu district, said military spokesman Brig. Udaya Nanayakkara. There were no immediate reports about any casualties. Elsewhere, soldiers pushed into Tiger territory in the Parappaankandal area of Mannar district and destroyed four rebel bunkers, killing 10 guerrillas, Nanayakkara said. Soldiers also destroyed two rebel bunkers in the northern district of Jaffna and killed two rebels, a defense official said on condition of anonymity because he was not authorized to speak to media. Rebel officials could not immediately be contacted for comment. A small explosion also hit a busy railway station in the capital, Colombo, slightly wounding one person, the military reported. The cause of the blast was not immediately clear. The Colombo area has been hit by a series of attacks in recent weeks, and the government has blamed the rebels. More than 70,000 people have been killed since the Liberation Tigers of Tamil Eelam began fighting in 1983 for an independent state for Sri Lanka's ethnic Tamil minority, claiming discrimination by the Sinhalese majority.