Nigerian billionaire Aliko Dangote, Africa's richest person, has tweeted to deny reports in some media outlets that he was one of the hostages in the Mali hotel siege.
Dangote says he was in Mali yesterday.
Here's what we know so far about the siege in Mali:
-- The attack began at 0700 GMT, according to Reuters.
-- As many as 10 gunmen have taken 170 people -- 140 guests and 30 employees -- hostage at the American-owned Radisson Blu hotel in Mali's capital, Bamako.
-- The gunmen shouted "Allahu Akbar," (God is great) as they stormed the hotel, a security source told Reuters.
-- At least three hostages are dead, according to an unnamed Malian minister who spoke to the AFP news agency.
-- The gunmen have released some hostages able to recite verses of the Quran, according to Reuters' security source.
-- AFP also says that around a dozen hostages have been escorted from the hotel.
-- A Malian minister told AFP that Mali security forces have stormed the hotel.
The official Twitter account of Mali's President's office has tweeted about the attack on the Radisson Blu hotel in Bamako.
The gunmen who attacked the Radisson Blu hotel in Mali are moving from floor to floor, a senior security source says.
An eye witness to the Mali hotel attack says that the gunmen arrived in a car this morning with diplomatic plates. They were wearing masks.
A number of Chinese guests are among those trapped in the Radisson Blu hotel in Mali's capital Bamako, China's state-run Xinhua news agency is reporting.
"A Chinese guest surnamed Chen told Xinhua via WeChat mobile app that he was among a number of Chinese guests trapped in the hotel," Xinhua said.
It is not known exactly how many Chinese guests are among those trapped in the hotel.
Sky News has tweeted some footage of the scene outside the Radisson Blu hotel in Mali's capital, Bamako.
The Rezidor Hotel Group, which operates the Radisson Blu in Bamako, has published a statement on the hotel's website.
It reads:
"The Rezidor Hotel Group...is aware of the hostage-taking that is ongoing at the property today, 20th November 2015. As per our information, two persons have locked in 140 guests and 30 employees. Our safety and security teams and our corporate team are in constant contact with the local authorities in order to offer any support possible to reinstate safety and security at the hotel. At this point, we do not have further information and continue to closely monitor the situation."
In a second statement shared with RFE/RL by email, Rezidor said:
We are extremely concerned about the situation in Mali and for the safety of all our guests and employees in the hotel. Our safety & security teams and corporate team are in constant contact with the authorities there, and will share further information with you when we have it.
The Radisson Blu is popular with ex-pats working in Mali.
One of those able to get out of the Radisson Blu in Mali was Sekouba Bambino Diabate, a popular Guinean singer. The singer released unharmed, according to Guinean news reports.
"I woke up with the sounds of gunshots and for me, it was just small bandits who came in the hotel to claim something," he told journalists, according to the BBC.
"After 20 or 30 minutes, I realized these are not just petty criminals."
The BBC says that the Qatari Al Jazeera TV has identified the militant group attacking the Radisson Blu hotel on Mali as the Ansar al-Din group, an "extremist military group that seeks to implement Islamic Sharia in Mali," according to the channel's correspondent in Mali.