A man at a Detroit airport said his family gave him 2 suitcases that turned out to contain $4 million in ketamine

• Customs officials found $4 million worth of Ketamine in a man's luggage in Detroit on December 13.
• The US Customs and Borders Protection said on Wednesday he was carrying two suitcases from France.

A man caught at the Detroit Metro Airport with two suitcases containing 110 pounds of ketamine said he got them from a family member, according to border authorities.

The man, a UK citizen, arrived in Detroit with the suitcases on December 13 via a flight from France, per the US Customs and Border Protection.

Customs officers put his baggage through an x-ray and physical search and found plastic bags filled with "large white crystals," the USCBP said on Wednesday.

With an estimated value of $90 per gram, that amount of ketamine is worth about $4 million on the streets, authorities added.

The unidentified man said a family member had given him the two suitcases, the USCBP said. The agency didn't say if customs officials could verify his claim.

Authorities seized the drugs and blocked the unidentified man from entering the US, the USCBP said.

He was sent back to France, it added.

"Travelers are encouraged to learn more about current regulations before attempting to bring certain items into the United States to avoid penalties, seizures, and even arrest," the border agency said.

Ketamine is a commonly used medical anesthetic that was found to have antidepressant effects when given to people suffering from severe depression. But it's also become notorious for being abused as a party drug for its hallucinogenic effects and dissociative sensations.

Some can get easily addicted to the drug, while others, including recently passed actor Matthew Perry, were found to have died at least in part from its use.

Perry was receiving ketamine treatment, but his autopsy report said the amount of ketamine found in his body could not have come from his last treatment — more than a week before his death.