Frustrations and dark discoveries mounted for a California town ravaged by a deadly and destructive mudslide.

Most of the people of Montecito are now under orders to stay out of town for two weeks. Santa Barbara County Sheriff Bill Brown on Thursday expanded what was known as the public safety exclusion zone to incorporate most of the town. That meant even those who had stayed behind would have to leave and those who entered the zone would be subject to arrest.

More than 1,200 workers taking part in the search and cleanup effort flooded into the town with a population of about 9,000.

A backhoe scooped up mud and rocks around buckled and flattened homes, while bulldozers cleared roads of tangled trees, muck and boulders. Tanker trucks were being used to haul off floodwaters sucked up from U.S. Highway 101, the crippled coastal route connecting Santa Barbara to Ventura.

Brown said the recovery effort has been hindered by residents who had stayed behind or tried to check on damage in neighborhoods where homes were leveled and car-size boulders blocked roads and littered properties.

Search-and-rescue workers found the body of the 18th victim, Joseph Bleckel, 87, before noon in his home near Romero Canyon, Brown said. It was the first death discovered since Wednesday.

The cause of Bleckel's death wasn't announced, but all other victims died from multiple traumatic injuries due to a flash flood and mudslides.

The seven missing people included Fabiola Benitez, the mother of Jonathan Benitez, a 10-year-old killed in the flooding.

Benitez lived with her sister-in-law, Marilyn Ramos, 27, who was asleep with her daughter, Kaelly, 3, when mud crashed through their Montecito rental home, carrying both to their deaths.

The husbands of both women and the 2-year-old son of Fabiola Benitez, were hospitalized with injuries, Ramos said.

Other crews toiled to clean up the massive wreckage of the slide and to repair power, water and gas lines.

The order to stay away was another difficult turn for those living in the Southern California town that has been subject to repeated evacuation orders in recent weeks, first because of a monster wildfire last month, then because of downpours and mudslides.

The Associated Press contributed to this report.