A strong earthquake that hit the Indonesian island of Java on Saturday has left at least 3,000 people dead, according to local officials.
The Swiss foreign ministry said there were no known Swiss victims, but it was trying to contact Swiss nationals in the area. Emergency aid experts are on standby.
In a statement, Swiss President Moritz Leuenberger and Foreign Minister Micheline Calmy-Rey expressed their condolences to the victims and to the Indonesian authorities.
The quake, which measured 6.2 on the Richter scale, devastated the densely populated region around the ancient city of Yogyakarta in central Indonesia.
It struck early in the morning while people were sleeping. Homes and buildings were flattened and roads and bridges were destroyed.
Almost 3,000 people have been injured and some are still trapped beneath the rubble, according to government and aid officials on the scene. President Susilo Bambang Yudhoyono has ordered the army to help evacuate victims.
The quake is said to be the country's worst disaster since the 2004 tsunami.
Yogyakarta is near the Mount Merapi volcano, which threatened to erupt earlier this month, forcing thousands of people to be evacuated. Experts said the tremor was not liked to the volcano.
Swiss on standby
The Swiss foreign ministry said there were no known Swiss victims and that it was in contact with its embassy in the Indonesian capital, Jakarta.
Spokeswoman Carine Carey said there were 20 Swiss nationals registered with the embassy who were living in the affected area and that officials were trying to reach them.
The Swiss Agency for Development and Cooperation (SDC) said they had contacted the Indonesian government and the United Nations to offer humanitarian aid.
"At the moment we haven't yet received any requests from aid from the Indonesian authorities or international organisations," said Thomas Jenatsch, spokesman for the SDC's Swiss Humanitarian Aid Unit.
"We are following the situation. For the moment, we have decided to send two of our colleagues who are based in Banda Aceh to Jakarta to evaluate the situation," he told swissinfo on Saturday morning.
A decision on whether to send aid from Switzerland is likely to be made later on Saturday. If experts are sent, they will leave Switzerland in the evening, added Jenatsch.
Bern has given $100,000 (SFr122,000) to the Indonesian Red Cross.
Swiss non-governmental organisations have already moved into action. Catholic charity Caritas, Protestant charity Swiss Interchurch Aid, and the Swiss Red Cross have pledged a total of SFr400,000 for emergency aid.
A representative of Interchurch Aid is already in Yogyakarta and officials from the other organisations are on their way.
Swiss Solidarity, the fundraising arm of the Swiss Broadcasting Corporation, swissinfo's parent company, said in a statement on its website that for the moment it would not be starting a collection.
The organisation, which often launches national fundraising campaigns after catastrophes, said that its partners on the ground would for the moment be ensuring aid from the neighbouring island of Sumatra, where post-tsunami work is being carried out.
swissinfo with agencies
After the 2004 tsunami, the Swiss Agency for Development and Cooperation sent emergency aid to Indonesia. The second phase involved support for several reconstruction projects, particularly in drinking water, in the province of Banda Aceh, the worst hit by the disaster.
Swiss Solidarity collected more than SFr40 million for post-tsunami reconstruction efforts in Indonesia.
Switzerland has long worked for a solution to the conflict in Aceh and supports projects in human rights, democracy and peace building as well as for economic cooperation.
October 8, 2005: 7.6 magnitude quake in Pakistan and India Kashmir region leaves at least 75,000 dead.
March 28, 2005: Tremor on the island of Nias, Indonesia, kills 905 people.
December 26, 2004: Quake near Sumatra causes a tsunami which hits a dozen countries in southeastern Asia. 220,000 dead or missing.
December 26, 2003: Quake in Bam, Iran, leaves 31,000 dead.
Swiss Solidarity, the fundraising arm of the Swiss Broadcasting Corporation, has launched an appeal to raise money for earthquake victims.
It announced on Monday that SFr100,000 was being made available immediately.
Donations can be sent to post office account: 10-15000-6, marked "Java", or made online (see link below).
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