LONDON -- Britain, Germany, the Netherlands and the United States issued ominous warnings on Thursday about threats to Westerners in Libya, in particular the unruly eastern city of Benghazi, less than a week after the deadly hostage crisis in neighboring Algeria.
Travel advisories issued by the foreign ministries of the three European countries did not elaborate on the precise nature of the threat, nor was it clear how many expatriates might be affected, but they warned their citizens to leave Benghazi immediately.
Hours later, the United States, which has admonished Americans to avoid Benghazi since the deadly attack on an American diplomatic compound there on Sept. 11, took note of the European advisories in an "emergency message" for United States citizens who might be in Libya or preparing to travel there.
"Although there is no specific information pointing to specific, imminent threats against U.S. citizens, the potential for violence and kidnappings targeting Westerners in Benghazi is significant," read the American message, posted on the Web site of the United States Embassy in Tripoli, the capital. "We strongly encourage all U.S. citizens to take appropriate precautions, as the security situation in Libya is volatile."
The message urged American expatriates to heed a Jan. 2 advisory issued by the State Department that broadened warning to avoid travel to Benghazi to include many other parts of Libya because of the lawlessness and instability that have troubled the country since the overthrow of Col. Muammar el-Qaddafi more than a year ago.
Benghazi, Libya's second-biggest city and the base of the revolution that overthrew Colonel Qaddafi's autocracy, has come to symbolize the problems in Libya and the impunity of regional militias, including some with Islamic militant ties who are believed to have played a role in the attack on the American Mission that killed four Americans, including Ambassador J. Christopher Stevens. Militants have also attacked other foreign targets recently, including an attempted ambush of Italy's consul earlier this month.
Britain's Foreign Office also warned against "all but essential travel" to several other Libyan cities besides Benghazi, citing a "high threat from terrorism" and a possibility of retaliatory attacks targeting Western interests in the region after the French military intervention in Mali, which preceded last week's Islamist militant attack on a remote Algerian gas field near the Libyan border.
Earlier this week, a senior Algerian official said several Egyptian members of the squad that attacked the Algerian gas complex were also among those who had attacked the American Mission in Benghazi.
The Egyptians were among 29 kidnappers killed by Algerian forces during the four-day siege of the gas plant, in which at least 37 foreign hostages and one Algerian died. Three militants were captured alive and one of them, under interrogation by Algerian security forces, recounted the Egyptians' involvement in both attacks, the Algerian official said.
"We are aware of a specific, imminent threat to Westerners in Benghazi," the Foreign Office advisory said. "We advise against all travel to Benghazi and urge any British nationals who are there against our advice to leave immediately."
The advisory also recommended that Britons who were still in Benghazi travel only in groups and only during daylight hours.
In other Libyan places, it said, "there is a high threat from terrorism. Attacks could be indiscriminate, including in places frequented by expatriates and foreign travelers." The advisory did not specifically link its warnings to the kidnappings in Algeria.
Foreign Office officials declined to elaborate on the exact nature of the threat. David Lidington, a minister in the Foreign Office, told the BBC that the government had based its warnings on "credible, serious and specific reports."
"Our advice to people is not to delay, just leave," he said.
The BBC also quoted Libya's deputy interior minister, Abdullah Massoud, as saying the Western reactions were unfounded.
As the crisis in Algeria unfolded, Prime Minister David Cameron of Britain repeatedly warned that Qaeda-linked extremists and other Islamist militants in North Africa presented a growing threat to Western interests.
"Just as we have reduced the scale of the Al Qaeda threat in other parts of the world, including in Pakistan and Afghanistan, so it has grown in other parts of the world," he said. "We need to be equally concerned about that, and equally focused on it."
During the Algerian hostage crisis, the kidnappers depicted their attack as linked to the French intervention in Mali, in turn provoked by a lightning advance south by Islamist extremists who have turned Mali's desert north into a separatist redoubt.
The Libya travel warnings came just as local Benghazi business leaders have been seeking to improve the city's attractiveness as a place for foreign companies to invest. They have been emphasizing Benghazi's proximity to Libya's most productive oil fields, among the biggest in Africa and the Middle East.
More than half a dozen major multinational oil companies based in Europe have operations in Libya, including ENI of Italy, Total of France and Repsol of Spain. None would disclose the number of Western expatriate employees they have in Libya, citing security reasons, but there was no immediate indication that they were hurriedly preparing to vacate the country.
"We remain in Libya and are in coordination with the government, which is making every effort to maximize safety," said Kristian Rix, a spokeswoman for Repsol. David Nicholas, a spokesman for BP of Britain, said the company has no production in Libya but had been exploring there and "has a small number of people in Tripoli."
Alan Cowell reported from London, and Rick Gladstone from New York. Stanley Reed contributed reporting from London. .world
This article originally appeared in The New York Times.