A 45-year-old Canadian man is facing charges after a heroin bust at the Halifax Stanfield International Airport on Valentine's Day.

Last Sunday, Canada Border Services Agency said officers discovered "inconsistencies" in a traveller's suitcase during a routine inspection. The man was travelling from Rwanda.

After taking the suitcase apart, the agents found a large package concealed in the liner of the suitcase.

"When we X-ray a bag, different products turn up different colours," said Colin Murchison, the chief of operations for the Canada Border Services Agency at the Halifax airport. 

"Any organic products, which can include narcotics, would show up as one colour while metals or more dense objects would show up as another."

Murchison said the package contained 4.8 kilograms of a substance which tested positive for heroin.

Border agents arrested the man and turned him and the narcotics over to the RCMP. 

Murchison said a "significant" seizure such as this does not occur very often in Halifax. He said there have been two such seizures in Atlantic Canada within the last five years — this one and a five-kilogram heroin seizure at the Port of Halifax in 2011.

At that time, the five kilograms of heroin seized had an estimated value of $2 million.