The LTTE's suicide attack on a naval convoy in Habarana and the Galle naval base in quick succession led to Sinhalese civilians attacking Tamil civilians in Galle town, Habarana and Matale on Wednesday.
But appeals by the government and Sinhala leaders and stern action by the police nipped the violence in the bud, reports reaching Colombo said.
In Galle town, Tamil shops were attacked the moment news spread about the LTTE's suicide attack on the Navy's Dakshina naval base at 7.45 am.
As the navy fought back in the harbour and destroyed the five suicide boats, the Army and Special Task Force scoured Galle town and its environs looking out for LTTE infiltrators.
But some local Sinhalese hoodlums had taken the law into their own hands and attacked Tamil-run shops.
In Habarana, where the LTTE killed 98 naval personnel in a suicide attack on a naval convoy, local Sinhalas stoned buses coming from the Tamil towns of Trincomalee and Batticaloa, and asked the Tamils in them to get down.
Likewise, in Matale, a town on the Colombo-Kandy road, Tamils were asked to get down from buses.
"They were harassed," a source said.
Fortunately, the incidents were minor. In Galle, the police clamped curfew and stopped traffic on the busy Colombo-Matara road to check vehicles.
President Mahinda Rajapaksa asked Defense spokesman Keheliya Rambukwella, prominent Sinhala leaders, and the police top brass, to go on the air and ask the people to be calm and avoid taking the law into their own hands.
"Any communal backlash will only help the LTTE, which has been wanting one," Rambukwella said.
"The LTTE thinks that a 1983 type of (anti-Tamil) riot will help its propaganda ahead of the talks in Geneva on October 28. But we are glad the people have remained calm and not fallen into the trap laid by the LTTE," he said.
The Deputy General Secretary of Sinhala-Buddhist party Jathika Hela Urumaya (JHU), Udaya Gammapilla MP, told Hindustan Times that he appeared on all the TV and radio channels to say that the Sinhala people should have confidence in the ability of the Rajapaksa government to handle the terrorist threat and not take the law into their own hands.
"While the LTTE attacked the Temple of the Tooth in Kandy, the Mahabodhi in Anuradhapura, and killed Buddhist monks in Arantawala, the Sinhala people never retaliated by attacking innocent Tamils because they distinguished between the Tamil people and the terrorist LTTE," Gammapilla said.
But during the regime of Ranil Wickremesinghe, the people had lost confidence in the ability of the government to tackle terrorism.
The peoples' confidence in the government should be restored and Sinhala leaders could help bring that about, he said.
About the incidents on Wednesday, Gammapilla said: "There were incidents here and there, of harassment of Tamils. But they were of a minor nature. However, government is keen that the people should be warned about the designs of the LTTE. I asked people to be calm and tolerant."
"It is vital for the common people to participate in the fight against terrorism, by remaining peaceful, tolerant, and vigilant. They should provide information to the police on suspected terrorist activities," Gammapilla said.