A United Nations report has revealed that Somali Islamist insurgents are making their own explosives to mount more frequent and deadly attacks.

The findings are a blow for internationally backed efforts to fight the al Shabaab insurgency, which has repeatedly carried out attacks in East Africa and launched dozens in Somalia this year despite a dramatic

The analysis was based on at least 20 attacks since July 2018, the report said.

It specify who did the analysis, but footnotes cited the U.N. Mine Action Service, the U.S. Federal Bureau of Investigation and experts who were not named but only identified by the dates on which they were interviewed.

The U.N. panel declined to comment, and the two organisations did not respond to questions from Reuters.

Somali government officials could not be reached for comment Luitenant Colonel Charles Imbiakha, spokesman for the African Union peacekeeping force AMISOM, said it could not comment because it had not seen the report.