In a statement, the Gibbon Conservation Society (GCS) said Indian authorities intercepted three attempts to smuggle the small apes into the South Asian country last year.

It said the most recent case which took place this month saw an Indian national nabbed for smuggling five infant Siamang gibbons, the largest of the endangered gibbon species, at the Mumbai airport. The suspect had travelled from Malaysia.

GCS asked how the smugglers had managed to slip through unchecked despite the rigid security protocols at Malaysia’s international airports.

“How did these gibbons pass through customs and airport security without being noticed?

“This raises grave concerns about oversight failures, corruption, or gaps in enforcement within Malaysia’s border security and airport surveillance,” it said.

GCS also said the frequency of these smugglings indicated a systemic failure in monitoring and enforcement, and called for a full-scale investigation into previous cases that might have gone undetected.

“This crisis must be addressed through transparent, international collaboration and stronger enforcement measures,” it said.

GCS also urged the wildlife and parks department (Perhilitan) and the natural resources and environmental sustainability ministry to take “immediate and decisive action” against the trafficking of gibbons and wildlife in general.

The NGO said the public deserved to know how Perhilitan and the ministry intended to tackle the issue.

“We urge the government to improve enforcement efforts in Malaysia’s jungles and at customs checkpoints to eliminate the loss of Malaysian wildlife,” it said.