The Sahel region of Africa is a ticking "time bomb" of terrorism and organised crime, a Moroccan police chief told AFP on Friday, a day after a suspected Daesh group-affiliated cell was busted.

"It was a dangerous cell primed to go into action at any moment," Abdelhak Khiame, head of the Central Bureau of Judicial Investigation (BCIJ), said in an interview at its offices in Sale, near Morocco's capital Rabat.

Five "extremists", aged between 29 and 43, were detained on Thursday in simultaneous operations at sites in Tangiers and the Rabat region, said the Central Bureau of Judicial Investigations.

Explosive belts, three kilogrammes of ammonium nitrate, electronic equipment and bladed weapons were seized in raids on homes and businesses of the suspects, the bureau said.

Khiame said the Daesh-affiliated group was plotting suicide attacks targeting "public personalities, military figures and the headquarters of security services" in the north African kingdom.

Ammonium nitrate is the chemical behind the August 4 cataclysmic Beirut blast.

Pledges of allegiance to the Daesh were discovered. Two of the suspects put up "fierce resistance", leaving a policeman with serious knife wounds.

The alleged head of the group, a 37-year-old fish salesman, had been convicted of a common law crime in 2004 and radicalised since.

Khiame said it was the first such large-scale bust since the 2003 Islamist suicide attacks in Casablanca, Morocco's economic capital that left 33 dead.

He warned that Daesh "has developed in the Sahel-Sahara region, with the conflict in Libya and in countries like Mali which do not control their security".

The Sahel covers western and northcentral Africa.

"Terrorist cells and terrorism are growing in the region but also organised crime networks, drug trafficking, weapons and human beings," said the BCIJ chief.

"All of this... makes the Sahel region, in my opinion, a time bomb."

Khiame said the dismantled cell had apparently had no direct contact with Daesh terrorists.

But "even if Daesh was defeated in the Levant, in the region of Syria and Iraq, its ideology... does not need territory, it can develop where it finds sympathisers,” he said, using an Arabic acronym for Daesh.

Daesh-inspired "cells underground act like sleeper cells which in most cases have no relationship to each other", he said.