Pol Maj-Gen Parinya Chansuriya, deputy metropolitan police chief, said yesterday that car and foot patrols would be increased in the vicinity of the US embassy.
The Metropolitan Police Bureau was also working with Special Branch police to gather intelligence on possible acts of terrorism in the country. The situation was normal, Pol Maj-Gen Parinya said.
Lumpini police station chief Rangsan Praditpol said current intelligence reports suggested no terrorism plots were under way.
Pol Col Rangsan said Lumpini police and Special Patrol and Operations Division or 191 police will be deployed to look after the US embassy as well as the residence of the US ambassador.
A foreign Muslim security source said the killing of the American diplomat in Libya was likely to trigger a symbolic retaliation against the Islamic world.
The measures could be serious considering the US is heading for a presidential election.
The attack on the US embassy in Libya was a religious response to hatred expressed against the prophet of Islam, he said.
The Libya attack carried the message that people holding different faiths should not do anything that provoked misunderstanding about other religions, the foreign diplomat said.
He predicted the consequences from the US embassy attack could be similar to those after the 9/11 incident which caused trouble to the Islamic world.
Malaysia's former prime minister Abdullah Ahmad Badawi condemned the embassy attack, saying the killing of the US diplomat was not the Islamic way.