London said Aug. 30 it was advising against travel to Lebanon, citing a risk of anti-Western sentiment in reaction to the possibility of a limited military strike on Syria.
The updated warning said British citizens should avoid a 3-mile zone along the Syrian border, the northern city of Tripoli and the southern suburbs of Beirut, considered strongholds of the Shiite Hezbollah movement.
Dozens of people were killed or injured in bombings in Tripoli and Beirut in recent weeks.
"Although tensions in the region have eased, the security situation can deteriorate quickly," the warning stated.
Lebanese authorities this week issued arrest warrants for two Syrian men suspected of plotting attacks against Hezbollah.
The Daily Star, an English-language newspaper in Lebanon, said the two men were suspected members of the rebel Free Syrian Army who used foreign funds to carry out attacks inside Lebanon.
"There is a high threat from terrorism," the British warning said. "Attacks could be indiscriminate, including in places frequented by foreigners like hotels and restaurants."
Hezbollah this year admitted to fighting alongside pro-government forces in the Syrian civil war.
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