UPDATE 2: An IAAF official gave a sit down interview with BBC explaining why the IAAF refused to let Isaac Makwala compete in the 400m final.



UPDATE 1: Isaac Makwala is trying to get into London Stadium and insists he is fit to race, but IAAF officials will not let him enter. He's reportedly being escorted to the IAAF office. 

"Isaac has been taken back to the hotel. We don't have any official communication with the IAAF. I haven't gone through the rules but we have a right to appeal. There has been no formal communication other than the medical communication. I met with Isaac this morning and this afternoon and he was ready for this race. He only has one symptom of the norovirus. Whether they are legally binding or not, we have not had any formal communication with the IAAF. He has been waiting for years to perform here. He has not been asked to be quarantined from other athletes in the hotel but he is not able to enter the stadium tonight," Falcon Sedimo of Botswana Athletics told the BBC.

#FreeMakwala IAAF officials refusing to let Isaac Makwaka enter stadium pic.twitter.com/bRWGDJSIaS

— FloTrack (@FloTrack) August 8, 2017

Isaac Makwala insists he's OK to race. He's even turned up at the stadium to prove it.

Could this IAAF decision have a worrying impact? pic.twitter.com/NhXLBw2UJP

— BBC Sport (@BBCSport) August 8, 2017

After missing the 200m heats at the IAAF World Championships on Monday, Isaac Makwala has been withdrawn from the men's 400m final due to a medical condition, the IAAF announced in a statement. 

The IAAF said the decision was made "on the instruction of the IAAF medical delegate," according to Reuters. 

Makwala reportedly admitted to vomiting before the 200m heats, but said he wasn't tested. 

"I could have run. I did my warm up well and I was ready to run. I feel ready to run today, tonight," he said. 

IAAF spokeswoman Jackie Brock-Doyle told BBC Sport that they "have to follow process for the health and well-being of all athletes."

The sprinter from Botswana was favored to win the 200m in London after running a world lead of 19.77 in July. Makwala was also expected to contend for a medal in the 400m after running a season's best of 43.84 at the Monaco Diamond League meeting. 400m Olympic champion Wayde van Niekerk is also competing in the sprint double. With Makwala out, van Niekerk's double gold pursuit appears to be within reach. 

After missing the first round of the 200m on Monday, Makwala expressed his disappointment on Facebook. 

"According to IAAF medics, I am apparently suffering from food poisoning which has affected several other athletes in the athletes' hotel," Makwala wrote. 

According to CNN, approximately 30 athletes have fallen ill to a  stomach bug which causes vomiting and diarrhea. Ireland's 400m hurdler Thomas Barr and several German and Canadian athletes also staying at the Tower Hotel have reportedly been affected and were forced to withdraw.