BAMAKO, Mali -- The prosecutor in charge of investigating last week's deadly assault on a luxury hotel in Mali's capital urged residents to keep an eye out for suspicious behavior.
Boubacar Sidiki Samake warned of heightened security threats as officials struggled to piece together details of how the attack was plotted and executed.
"People need to start watching what is happening with their neighbors," he said Tuesday, adding that future attacks are more likely to be prevented if Malians "changed their behavior."
Samake provided little new information about the investigation of Friday's assault that killed 21 people, including two attackers.
On Monday, state television broadcast the photos of the two gunmen killed in the attack and urged anyone with information to come forward.
The first Islamic extremist group to claim responsibility -- Al-Mourabitoun, or The Sentinels -- issued an audio recording Sunday purporting to identify the gunmen, using names that suggested they were Malian. But officials have yet to confirm their identities and said they did not know whether the attackers were based in Bamako before the attack.
Samake said the gunmen were spotted to the west of the Radisson Blu hotel at 6 a.m. Friday morning, about an hour before the attack began, sitting with two suitcases containing the Kalashnikov assault rifles they used in the attack.
On Tuesday, a United Nations police official displayed the assault rifles to journalists in Bamako, but he said they had been handled by too many people to yield useful fingerprints.
"With the serial numbers ... we can trace whether these come from the Malian army stock, which was looted in 2012, or if they were imported illegally," said the official, who gave only his first name, Laurent, in line with the policy of his division.
Officials are still trying to determine how the victims were killed in the hotel, Samake said.
Noting that Islamic extremists in March shot up a Bamako bar popular with foreigners, Samake said security threats in the city were "very high."
U.N. spokesman Stephane Dujarric said Monday that the U.N. mission in Mali had offered help with the investigation and had joined Malian security forces in conducting night patrols in the city.
On Tuesday, Mali's U.N. mission reported that a civilian staff member was killed in the northern region of Timbuktu when a vehicle traveled over an explosive device. The explosion occurred just before noon about 15 miles west of Timbuktu, mission spokesman Olivier Salgado said.
It is the same region where gunmen in July ambushed a U.N. convoy and killed six peacekeepers from Burkina Faso in an attack claimed by al-Qaida in the Islamic Maghreb.
Northern Mali fell under control of Islamic extremists in 2012, prompting a French-led military intervention in early 2013 that drove them from cities and towns. The north remains insecure, however, and the U.N. mission in Mali is the most dangerous in the world, with more than 40 peacekeepers killed since it was established in April 2013.
Information for this article was contributed by Edith M. Lederer of The Associated Press.
A Section on 11/25/2015