At least eight people were killed and 24 were missing as heavy storms lashed southern Morocco, causing flash floods, the authorities said on Sunday.

It said the "exceptional" storms swept across the regions of Guelmim, Agadir, Ouarzazate and Marrakesh, and a search was under way for the missing.

The Arabic-language dailies Al Massae and Al Ahdath gave death tolls of 16 and 22 dead respectively.

Some 130 all-terrain rescue vehicles and 335 Zodiac inflatables and other boats were being used, the interior ministry said, in a statement carried by the North African country's MAP news agency.

The national weather service warned that an alert over more heavy rainfall would remain in place until midday on Monday.

A flash flood near Guelmim, 200 kilometres (125 miles) south of Agadir, killed six people including a nine-year-old girl and left 24 missing, MAP cited a ministerial source as saying.

It said around 100 mud-brick homes were partly or totally destroyed in the south, and 100 roads cut off, including six national highways.

Flash floods are common in Morocco, where four children drowned in the south in September when they were swept away.