Heavy ash contaminates water supplies while volcanologists say activity could continue for weeks

Leaders of volcano-racked St Vincent have warned that water is running short as heavy ash contaminates supplies, amid estimates that the eastern Caribbean island will need hundreds of millions of dollars to recover from the eruption of La Soufrière.

Between 16,000 and 20,000 people have been evacuated from the island’s northern region, where the exploding volcano is located, with more than 3,000 of them staying at more than 80 government shelters.

An explosive eruption rocked La Soufrière volcano on the eastern Caribbean island of St Vincent on Friday following mandatory evacuation orders from the local government. There were no immediate reports of casualties from the burst that occurred just four days short of the 42nd anniversary of the last eruption.

• St Vincent rocked by explosive eruptions at La Soufrière volcano
  

National Emergency Management Organisation warned residents to leave and said ash plume had reached 20,000ft

The Caribbean island of St Vincent has been rocked by a string of explosive eruptions at La Soufrière volcano, which spewed clouds of ash miles into the air a day and forced thousands to flee for safety.

Related: Saint Vincent orders evacuations as volcanic eruption appears imminent