Some families in Spain were planning funerals on Tuesday, days after their relative’s corpses were found in the wreckage of floods that killed at least 215 people. Others, caught between grief and hope, were still waiting for news. They wondered if maybe, miraculously, a missing relative could still be alive somewhere in the muck.

A full week after the catastrophic rains, the government has still not published an official public figure on the number of missing.

“We want to be very cautious,” Óscar Puente, the Spanish transport minister, said in a radio interview on Monday. Officials have tried to dispel unsubstantiated reports that almost 2,000 people are missing; Mr. Puente said that cabinet members had discussed a “fairly low figure, but we do not trust that this figure corresponds to reality.”

Many families, though, have not waited for the government to start raising the alarm.

As volunteers came with tractors and brooms to help clean up, others took to the internet. Social media pages have lit up with pictures of the disappeared. One crowdsourced map of the area around Valencia lists their last-known locations. Another collects real-time information about the things residents need most urgently.

“We had to act quickly, because people were without basic resources,” said Jorge Sáiz, 32, who built that aid map with his wife, Sandra Navarro, 31.

Last week, a social media account began sharing photos and information about missing people. The page is called “DANA Desaparecidos,” which roughly translates to “Missing From the Storm.”