14:55 The US ambassador in Kenya says the United States is working closely with Kenyan authorities following the extremist attack in Nairobi this week.US Ambassador Robert F. Godec in a statement on Thursday also dismissed "false reports on social media" that the US knew about the attack in advance and warned Americans to stay away from the DusitD2 complex before it was attacked on Tuesday.Godec says that "we deplore the spread of false information in the wake of this tragedy, which only serves to hamper ongoing efforts to defeat terrorism."___14:50 A security company confirms that two employees were killed in this week's extremist attack on a luxury hotel complex in Kenya's capital.Michael Ruto with Senaca International Security Ltd describes the victims as "very good officers." The company provides security for the DusitD2 complex that was stormed by several gunmen on Tuesday.Kenyan authorities are still sweeping the complex for explosives the attackers might have left behind. The assault killed 21 people plus the five attackers.The al-Shabab extremist group has claimed responsibility.___14:25 Kenyan officials say they can safely host an international athletics competition in Nairobi next year despite concerns over the attack by extremist gunmen this week.Local media reported on Thursday that officials told a visiting delegation from the International Association of Athletics Federations that Kenyan security will ensure a successful IAAF World Under-20 Championships in July 2020.Senior official Hassan Noor assured IAAF delegates that the deadly assault on the DusitD2 complex on Tuesday was an "isolated incident" and that they can move around Nairobi without fear, according to Kenya's Daily Nation newspaper.The newspaper says the IAAF delegates finished meetings on Thursday after inspecting a stadium and visiting planned accommodation for athletes, officials and media.___14:05 Kenyan authorities say there are no longer any cases of missing people following an extremist attack on a hotel complex in Nairobi.The Kenya Red Cross said on Thursday that all 94 cases of people reported to be missing had been "closed positively."Police say 21 people, plus five attackers, died in the attack on the DusitD2 complex in the Kenyan capital.___12:45 Kenya's information minister says the government's quick reaction to a deadly extremist attack in Nairobi this week reflects improvements in its ability to respond to such brazen assaults on civilian targets.Joseph Mucheru said on Thursday that the reaction of authorities when gunmen attacked the DusitD2 hotel, office and shopping complex on Tuesday was "much better handled, communicated" in comparison to the 2013 attack on the nearby Westgate Mall."The speed, the response and the conclusion of this matter was swift," Mucheru said.Kenyan police said 21 people, plus five extremists, died in the latest attack. Kenya's president declared that the security operation to retake the complex was over around 20 hours after it started.The al-Shabab group claimed responsibility, showing it can still strike despite heavy military pressure in Somalia.Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.