The explosion set cars ablaze and broke the windows of some buildings, they said. There was no word on casualties.
Yesterday, a woman was killed when an explosive device planted under a parked car detonated by a popular shopping mall in the mainly Christian east of the capital. At least 10 people were wounded by flying glass.
In the north of the country, Lebanese troops battled Islamist militants at a Palestinian refugee camp for the second day on Monday. So far, 79 people have been killed in Lebanon's bloodiest internal fighting since its 1975-90 civil war.
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