UNITED NATIONS — Chemical weapons experts are gathering in the Netherlands and will depart "within days" for Syria to investigate three allegations of alleged chemical weapons use, the United Nations said Thursday.

U.N. spokesman Martin Nesirky said Sweden's Ake Sellstrom will lead a team of about 10 experts from the Organization for the Prohibition of Chemical Weapons and the World Health Organization.

The U.N. gave a green light for the investigation Wednesday following an "understanding" reached between the Syrian government and U.N. disarmament chief Angela Kane and Sellstrom who visited Damascus last week.

The team will visit the village of Khan al Assal, a village on the southwestern outskirts of the embattled city of Aleppo, which was captured by the rebels last week and was under attack by government forces Wednesday. The government and rebels blame each other for a purported chemical attack on the village on March 19 that killed at least 30 people.

Nesirky said the team will also investigate two other incidents "where the evaluation of available information has indicated an onsite investigation is warranted." He said their locations "are being kept confidential as a safety and security precaution."

The mandate of the investigation team is to report on whether chemical weapons were used, and if so which chemical weapon, but not to determine the responsibility for an attack.

U.N. Mideast envoy Robert Serry told the Security Council last week that the U.N. has received 13 reports of alleged chemical weapons use in Syria.

President Bashar Assad's government initially asked the U.N. to investigate the Khan al Assal incident. Britain, France and the U.S. followed with other allegations of chemical weapons use in Homs, Damascus and elsewhere.

The announcement of the investigation capped more than four months of behind the scenes talks aimed at getting chemical experts on the ground, with Syria trying to limit the probe just to Khan al-Assal and the U.S., Britain and France pressing for a broader investigation.

Nesirky said the U.N. team is assembling in The Hague, where the Organization for the Prohibition of Chemical Weapons is based, "and will be ready to depart once the remaining logistical and legal details for the mission have been finalized."