Polisario says police chief killed in Western Sahara
"The commander of the national gendarmerie Addah al-Bendir fell on Tuesday as a martyr on the field of honour," the pro-independence movement's defence ministry said in a statement.
He "was on a military mission in the liberated zone of Rouss Irni, in Tifariti," located in the north in Polisario-controlled territory, it added, without elaborating on the circumstances surrounding his death.
Western Sahara is a former Spanish colony, mostly under Rabat's control, where tensions between Morocco and the Polisario Front have simmered since the 1970s.
Morocco has offered autonomy but maintains the territory is a sovereign part of the kingdom.
The Polisario fought a war of independence with Morocco from 1975 to 1991 and its leaders proclaimed the Sahrawi Arab Democratic Republic (SADR) in February 1976.
Wednesday's statement said Bendir was born in the Tiress region in 1956, and joined the Polisario Front in 1978.
There was no immediate confirmation of the death from Moroccan authorities.
Several Moroccan media outlets had reported his demise on Wednesday morning, purportedly during a Polisario-led operation "to the east of the wall" of sand which separates the two sides.
Tensions rose sharply in November when Morocco sent troops into a buffer zone to reopen the only road leading from Morocco to Mauritania and the rest of West Africa, after the separatists had blocked it the previous month.
The Polisario responded by declaring a 1991 UN-backed ceasefire null and void, arguing the road had not existed when the truce was signed and was therefore illegal.
The two sides have since exchanged regular fire along the demarcation line, though claims are difficult to independently verify in the hard-to-access area.
The Algeria-backed Polisario Front controls about a fifth of the vast, arid territory, and is demanding a promised UN-run referendum on self-determination.
In December, Morocco normalised ties with Israel in a diplomatic quid pro quo that saw Washington back Moroccan rule over Western Sahara, a move that infuriated the Polisario.