Fifteen airline flight crew members have been arrested after cocaine was found in baggage — the second such incident in a month.

The South African Airways employees were detained after 11 pounds of the drug — worth about $355,000 — was discovered in a bag on a flight from Johannesburg.

Crew members were arrested after U.K. Border Agency officers made the discovery at HeathrowAirport in London.

Those in custody were being interviewed by HM Revenue & Customs investigation officers.

On Jan. 21, a 15-member flight crew from the same airline was detained after cocaine and cannabis worth $440,000 was found in three bags.

The 10 women and five men questioned over the incident were released on unconditional bail.

They were due to report back to HMRC investigators at Heathrow Police Station on March 23.

A spokesman for HMRC said it was "very, very unusual" for two separate crews to be arrested in such similar circumstances within such a short period of time.

He added: "We were surprised to find another (haul)."

South African Airways was unavailable for comment.

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