Anti-narcotics detectives based at the Jomo Kenyatta International Airport seized Sh3.2 million worth of heroin and arrested the trafficker, a Polish national.
The suspect identified as Arkadiusz Stanislaw, 37, was arrested at JKIA's Terminal 1C moments before boarding a Hungary-bound Egyptian airline.
The drugs were found stashed in his luggage, police said.
The trafficker who was destined for Hungary's capital (Budapest) will be charged with possession and trafficking of narcotics.
Police are however yet to establish the source of the narcotics found on the man.
In 2019, then European Union Ambassador to Kenya Simon Mordue said the Kenyan port of Mombasa accounted for 30 per cent of illegal heroin smuggled into the EU market.
Most of the heroin in the country originates from Afghanistan through the Indian Ocean while cocaine originates from South America.
Stanislaw's arrest comes at a time when a crackdown on drug traffickers and unlicensed brewers has been heightened, a move by the government to foil the illicit trade in the country.
Some Kenyans have been arrested with narcotics in India raising concerns there could be more of the drugs locally.
The Director Anti-Narcotics Directorate Margaret Karanja warns that all those caught up in the ring of traffickers and peddlers will be treated with the severity of the law, despite their roles in the trade.
