A new round of factional fighting last night in Lebanon's northern port of Tripoli left at least 25 persons wounded, police said, and Syrian Foreign Minister Abdul Halim Khaddam paid a surprise visit there today to seek a truce.

Khaddam and former Lebanese prime minister Rashid Karami, a leading local political figure, met for several hours and afterward told reporters that a cease-fire had been agreed. A Reuter correspondent in the city reported that the continual sniper fire that marked the morning slackened off in the afternoon, and a degree of calm returned. Numerous earlier cease-fires have quickly broken down, however.

Tripoli, Lebanon's second largest city, is under the overall control of Syrian troops who intervened in Lebanon during the 1975-1976 civil war.

More than 30 people have been killed and 150 wounded in more than a week of fighting between militiamen of the Syrian-backed Alawite Moslem Arab Democratic Party and those of a rival coalition of Sunni Moslem parties called the National Resistance Movement, which is described as anti-Syrian. Police said multiple rocket launchers were used for the first time in the clashes in slum neighborhoods where the fighting has raged. "Shells and rockets rained on Tripoli in a night-long inferno," Beirut state radio reported.

In other developments, the Christian "Voice of Lebanon" radio station reported that three persons were killed and three others injured when a car bomb exploded outside a hotel in the coastal town of Safra northeast of Beirut.

In Tel Aviv, the military command reported that three Israeli soldiers were wounded when their ammunition truck caught fire in a village in the Chouf mountain area southeast of Beirut.