The death toll from devastating floods in eastern Spain has risen to 158, regional authorities and emergency services have said, as the country began 3 days of mourning and the prime minister, Pedro Sánchez, urged people to stay at home, writes The Guardian.

With forecasts of more bad weather prompting storm alerts farther north, Sánchez urged residents on Thursday to “please, follow the calls of the emergency services … Right now the most important thing is to save as many lives as possible”.

Officials in the stricken eastern region of Valencia said 155 bodies had been recovered there, with 3 deaths also reported from the Castilla-La Mancha and Andalusia regions. The toll makes the disaster the deadliest episode of flooding in Spain’s modern history.

Authorities have not disclosed how many people are still unaccounted for but the defence minister, Margarita Robles, earlier said the death toll was expected to rise further given some areas remain inaccessible to rescuers.

Flags flew at half-mast on government buildings and a minute of silence was observed nationwide after the flash floods battered Valencia’s infrastructure, sweeping away bridges, roads and railway tracks and submerging farmland.

Survivors told of walls of rushing water that turned narrow streets into death traps and spawned torrents that poured into the ground floors and garages of houses and apartment blocks.

Angry people in several towns said mobile phone alerts had not been sent out until 8pm on Tuesday, when serious flooding had already started in some areas – and several hours after the national weather service, Aemet, had issued a red alert for exceptionally heavy rains.