BAMAKO, July 18 (Reuters) - Three Chinese nationals and two Mauritanians were abducted from a construction site in northern Mali on Saturday when gunmen raided the site for equipment and took hostages, the army said. The raid took place 55 kilometres (34 miles) from the town of Kwala, a regular transit point for companies moving through Mali"s desert north, the army said in a statement. Later that evening, gunmen attacked a road checkpoint in the country"s central San region, around 400 km from Bamako, and killed three civilians, the army said in a second statement. No group has yet taken responsibility for either attack. Parts of Mali have been mired in violence since 2012, when several insurgent groups launched campaigns against the Malian government for greater autonomy. The conflict, which has since been co-opted by jihadist militants linked to al Qaeda and the Islamic State, has displaced hundreds of thousands. Those kidnapped on Saturday are employees of Chinese construction firm Covec and Mauritanian road-building company ATTM, which had been developing the site while under the protection of a private security company, the army statement said. The attackers also made off with five pick-up trucks before setting fire to much of the site, destroying a crane, dump trucks and other equipment owned by the companies, the statement said. Kidnappings are a common fixture of the war in Mali, with foreign nationals in particular regularly targeted by militants hoping to obtain ransoms for their release. United Nations Secretary-General Antonio Guterres asked the Security Council to authorise additional troops for Mali"s peacekeeping mission in response to rising violence by Islamist militants, according to a report seen by Reuters on Friday. read more Meanwhile, former colonial power France has announced plans to begin drawing down its 5,100-strong taskforce that targets the militants across West Africa"s Sahel region. read more