DAKAR (AFP) - Senegalese police have arrested a Malian man after seizing more than a tonne of marijuana amid a spate of drug finds in the west African country, local media said on Wednesday.

The haul was "carefully concealed in 21 woven fibre bags (weighing) a total of one tonne and 10 kilogrammes" the Senegalese Press Agency reported, citing Senegal's anti-drug trafficking unit Ocrtis.

Agents made the discovery on Monday near Dakar, the report said, arresting a resident of Malian capital Bamako, who is alleged to have admitted importing drugs from Mali.

The Malian was taken in custody for suspected international trafficking of marijuana, the report said.

The major haul comes as Senegal police reportedly made several other drugs discoveries.

Local media, citing narcotics police chief Mame Seydou Ndour, reported a second seizure of 260 kilogrammes of marijuana in a suburb of Dakar on Monday.

Senegalese police also arrested an agent from Ocrtis, who was caught with wraps of cocaine he was allegedly about to sell to a Nigerian, according to several local media reports.

"This is an unfortunate case that we have witnessed. The investigation is ongoing. It's a corrupt agent who has been implicated," Interior Minister Abdoulaye Dadouda Diallo told reporters.

The case is second recent high-profile scandal involving the agency to make the headlines.

Former Ocrtis chief Cheikh Sadibou Keita was sacked last year after wrongly accusing a predecessor of being implicated in the resale of seized drugs with the complicity of Nigerian traffickers.

The United Nations Office on Drugs and Crime (UNODC) said more than 20 major drug hauls were carried out in West Africa - mainly at sea - between 2005 and 2007.

Thousands of kilogrammes of cocaine were seized, including more than 11 tonnes in 2007 alone.