Only six Swiss citizens were able to leave Beirut by ferry on Monday night out of a group of 40 nationals wanting to leave the embattled Lebanese capital.
Israeli forces ordered the ship to leave the harbour early, fearing that they could not guarantee security after nightfall.
The Greek ferry chartered by France arrived in the Cypriot port of Larnaca early on Tuesday morning.
About 900 passengers, including around 750 French, were evacuated according to French officials. Three hundred other people were due to have caught the ship but the operation was curtailed when night fell for security reasons.
Swiss foreign ministry spokesman Jean-Philippe Jeannerat confirmed that only three or four reached the port of Larnaca on Tuesday morning.
Earlier on Monday the ministry had announced that 40 Swiss were among about 1,200 foreigners being evacuated on board the ferry.
"When our ambassador François Barras and staff found out that the ship was leaving and many people were blocked in Beirut harbour, they immediately went there," Jeannerat told French-language Swiss radio.
"Some of them could be put up in hotels... some were even put up at the embassy."
Jeannerat added that he could not say when other evacuation operations would take place. This depended on the intensity of Israeli bombing.
Foreigners seeking to be evacuated have besieged embassies and foreign organisations in Beirut.
Barras told Swiss public radio on Monday that hundreds of Swiss citizens wanted to escape Lebanon. He said that most of these people were dual nationals who only wanted to leave temporarily, but warned it would not be possible to evacuate all of them for a few days.
Of particular concern were 55 Swiss citizens trapped in southern Lebanon, where the Islamic Hezbollah militants – Israel's real targets – are firing rockets at the port of Haifa and other areas of northern Israel.
According to Barras, the first "refugees" from the area have already arrived at the Swiss embassy. He added some of them – those living near the port of Tyre – had lost "everything".
A German pastor in the capital told the Swiss News Agency that many foreigners, including several Swiss, had sought help in his evangelical community.
"Many are panicking and want to get out of Lebanon as quickly as possible," said Uwe Weltzien, adding that several people were clearly traumatised by their experiences.
The Swiss foreign ministry is attempting to deal with the situation by sending extra staff to Lebanon to help the Swiss still there. Besides the maritime route, it is also considering sending more people by road to Syria.
According to the latest information from the ministry, around 136 Swiss nationals were evacuated to Syria over the weekend, and hundreds more are in hotels in Beirut awaiting transport out of the country.
Most foreign embassies, including that of Switzerland, have been advising their nationals to stay where they are until safe passage can be arranged for them.
Despite calls by the United Nations for a ceasefire, Hezbollah militants were on Monday stepping up both their attacks and their rhetoric, while Israel continued its bombardment and denied media reports that it had any plans to halt the offensive.
Israel also said it was too soon to consider a UN plan to send a multinational security force to Lebanon.
swissinfo with agencies
The Swiss foreign ministry says there are 838 Swiss nationals registered as resident in Lebanon, of which 713 hold dual nationality.
The number of tourists is not clear, but could amount to "several hundred".
Family members can contact the foreign ministry for further information on +41 31 324 98 08.
The fighting - the worst since Israel invaded southern Lebanon in 1982 – was triggered after Hezbollah seized two Israeli soldiers in a cross-border raid last week.
The Islamic militant movement is part of the Lebanese government and is backed by Syria and Iran.
So far more than 200 people in Lebanon – most civilians – have been killed, and much of the country's infrastructure destroyed, including Beirut airport and the motorway to Damascus.
Twenty-four Israelis have died, including 12 civilians hit by Hezbollah rocket attacks.