Around 40 African migrants took advantage of flood damage at the border to cross into Spain's North African enclave of Melilla from Morocco on Monday, police and local government officials said.

Seventeen people were detained shortly after entering Spanish territory while the rest managed to enter the city of roughly 70,000 people which was lashed by heavy rain and strong winds on Sunday, a local police spokeswoman told AFP.

A total of 65 migrants tried to enter through a lock in a flood channel near the border post of Beni-Enzarhich which was damaged by the rough weather and could not be closed properly, she said.

Earlier on Monday the Spanish government's office in Melilla said about 30 African migrants tried to cross into Melilla from Morocco at the border checkpoint and an unknown number had succeeded.

Melilla has boosted police presence along its border with Morocco after Sunday's heavy rains destroyed a 30-metre (yard) stretch of wire fencing set up to keep illegal immigrants out of the city.

The rain also flooded streets, knocked down trees and disrupted maritime and air traffic for several hours on Sunday.

The border barriers between Melilla and Morocco have been regularly assaulted in the past by migrants trying to enter Spanish territory, although tighter border security has reduced the frequency of such attempts.

In 2005, 14 migrants were killed while they tried to cross the border. They included several shot by Moroccan or Spanish security forces during assaults on the borders of Melilla and Ceuta, another Spanish enclave in North Africa. Both Ceuta and Melilla are claimed by Morocco.