Kenya's Lucy Wangui Kabuu has been provisionally suspended by the Athletics Integrity Unit following a positive drugs test ©Getty Images

Kenya are facing a fresh wave of doping problems after distance runner Lucy Wangui Kabuu and sprinter Boniface Mweresa were each been suspended following failed drugs tests.

The Athletics Integrity Unit (AIU) announced today that Wangui was provisionally suspended after a failed test for banned narcotic, morphine.

The 34-year-old has twice finished in the top 10 of the Olympic 10,000 metres at Athens 2004 and Beijing 2008 and won the Commonwealth Games gold medal at Melbourne in 2006. 

Her best success in recent years has come over the marathon distance, where she set a personal best of 2 hours 19min 34sec in Dubai in 2012.

This time ranks her 13th on the all-time list over 26.2 miles.

Wangui had returned to action this year and won the Milan Marathon in April.

"The AIU has issued a Notice of Charge against Lucy Wangui for a violation of Article 2.1 of the Anti-Doping Rules," tweeted the body, who administer all anti-doping matters on behalf of the International Association of Athletics Federations.

"The #Kenyan #marathon runner is has been Provisionally Suspended from all competition."

Mweresa, meanwhile, was dropped from the Kenyan team for this week's African Athletics Championships in Asaba after a reported failure for an unspecified substance.

The 24-year-old, winner of a 400m silver and 4x400m relay gold at the 2015 All-African Games in Brazzaville, reportedly registered the failure at the Kenya Defence Forces Championships in Nairobi.

He competed at this year's Commonwealth Games in Gold Coast, reaching the semi-finals of the 400m. 

Mweresa maintains his innocence and has reportedly blamed the failure on a supplement.

Kenyan sprinter Boniface Mweresa, pictured competing at this year's Commonwealth Games in the Gold Coast, has been implicated in a doping scandal after testing positive, although he blames a supplement ©Getty Images
Kenyan sprinter Boniface Mweresa, pictured competing at this year's Commonwealth Games in the Gold Coast, has been implicated in a doping scandal after testing positive, although he blames a supplement ©Getty Images

Kenya and Ethiopia head a list of nations categorised by the IAAF last month as being the most at risk of doping.

Former Olympic and world 1500 meters champion Asbel Kiprop is among leading Kenyans to have recently failed a drug test for EPO (erythropoietin).

Other notable Kenyans to have failed tests include three-time Boston Marathon champion Rita Jeptoo and Jemimah Sumgong, the Olympic marathon gold medallist at Rio 2016. 

Reigning Olympic steeplechase champion Bahraini Ruth Jebet, who trains and lives and is originally from Kenya, has also been suspended since February following an EPO failure.