The Lebanese navy has reportedly intercepted a ship loaded with three containers of weapons destined for Syrian opposition forces.
The cargo vessel, which originated from Libya, was found on Saturday. Pictures released by the army showed dozens of crates inside the containers, some of them filled with belts of heavy ammunition and rocket-propelled grenades.
Military prosecutor Saqr Saqr said an investigation was under way, adding that the 11 crew members were being questioned by Lebanese military police.
Labelling on one box said it contained fragmentation explosives, and several identified them as coming from Libya.
A security official said the Sierre Leone-flagged Lutfallah II was bound for members of the Free Syrian Army, an umbrella group of fighters trying to overthrow the government of Bashar al-Assad, the Syrian president.
The ship's officers had previously obtained a permit to enter the port of Tripoli in northern Lebanon before being stopped by the navy on Thursday night.
The ship was towed to Selaata, a small port some 50km north of Beirut, Lebanon's capital, on Saturday. Three army trucks had reportedly left Selaata for Beirut with the seized cache of weapons, escorted by eight jeeps and a helicopter.
Syrian authorities have repeatedly charged that weapons are being smuggled from Lebanon to rebels fighting to overthrow Assad.
Also on Saturday, state media said gunmen in inflatable boats attacked a military unit on Syria's Mediterranean coast..
| Lebanese army released pictures
of seized ammunitions [AP]
The official SANA news agency said several fighters and soldiers died in the battle that followed the coastal attack
near the northern port of Latakia, 35km south of the Turkish border.
"The fighting ... resulted in the death and wounding of a number of military personnel while the number of those killed from the terrorist group was not known because they attacked the military unit at night," SANA said.
Meanwhile, a veteran Norwegian peacekeeper was on his way to Damascus to take charge of a UN mission overseeing the country's shaky ceasefire, which has been violated by both government forces and opposition fighters.
Major-General Robert Mood takes over a mission that faces major obstacles and doubts before the full 300-member force approved by the UN Security Council has even gathered.
Mood himself has highlighted the "abyss of suspicion" between Assad and the opposition. The uprising against Assad's rule has killed more than 9,000 people since March last year, according to UN figures.
State media reported on Friday that nine people were killed by a suicide bomber in the Damascus neighbourhood of al-Midan.
In the wake of the deadly blast and several other, smaller blasts in the capital, official Syrian newspapers accused UN Secretary General Ban Ki-Moon of "encouraging terrorists" and UN-Arab envoy Kofi Annan, the architect of a six-point peace plan, of failing to deliver on his promises.
"Why don't they request the withdrawal of these terrorists?" state newspaper al-Thawra wrote "Why not mention their presence, their role and their supporters and financiers? And the killers who made them and allowed them to infiltrate our streets and exist among us?"
In-depth coverage of escalating violence across Syria
Government newspaper Tishrin wrote in an editorial that "the secretary-general avoids talking about abuses by armed groups and focuses his blame solely on Syria, as usual. He encourages these groups to continue to commit more crimes and terrorist acts, which at the end of the day, the Syrian citizen pays for with his life, blood and security."
The paper asserted that Friday's blast in al-Midan proved that "armed terrorist groups" are continuing their aggression in violation of the UN ceasefire and in spite of the arrival of the international observers.
"Arab and international silence regarding the terrorist bombings in Syria [and] encourages the terrorists to repeat their crimes amid applause from countries such as Qatar, Saudi Arabia and Turkey."
Also commenting on the explosions, Russia on Saturday condemned what it called "barbaric" attacks in Syria.
Russia has protected Assad by blocking two UN Security Council resolutions condemning the government's crackdown on the opposition.
In a statement, the foreign ministry accused opponents of the Syrian government of seeking to scuttle Annan's peace plan, which Moscow has backed in the UN Security Council.
"Attempts by the irreconcilable opposition to increase tension even more and incite violence cause particular alarm," the statement said.
"[T[he aim is clear: to ruin a solution in Syria based on Annan's plan, which has begun to be implemented," it added, urging all forces inside and outside Syria to "decisively rebuff terrorists" and ensure they receive no support.