JOPLIN, Mo. >> A massive tornado that tore a six-mile path across southwestern Missouri killed at least 116 people as it smashed the city of Joplin, ripping into a hospital, crushing cars and leaving behind only splintered tree trunks where entire neighborhoods once stood.

City Manager Mark Rohr announced the new death toll Monday afternoon. He said seven people had been rescued, and search and rescue efforts were still going on.

Gov. Jay Nixon said he was "optimistic that there are still lives out there to be saved."

The rescuers’ work has been made more difficult by downed power lines, jagged debris, blocked roads and a thunderstorm that brought strong winds, heavy rain and hail early Monday. Crews found bodies in vehicles the storm had flipped over, torn apart and left crushed like empty cans. Triage centers and temporary shelters quickly filled to capacity. At Memorial Hall, a downtown entertainment venue, emergency workers treated critically injured patients.

Officials have estimated that 2,000 buildings were damaged. Among the hardest-hit was St. John’s Regional Medical Center, where a doctor said at least four people were killed. Staff members had hustled patients into hallways before the storm struck the nine-story building. The winds blew out hundreds of windows and left the facility virtually useless.

Dr. Jim Roscoe said he didn’t know whether those killed were staff or patients. He said colleagues who were injured worked all night long.

An unknown number of people were injured, and officials said patients were sent to any nearby hospitals that could take them.

Joplin Fire Chief Mitch Randles estimated the damage covered a quarter or more of Joplin, a city of about 50,000 people some 160 miles south of Kansas City. He said his home was among those destroyed.

Police officers staffed virtually every major intersection as ambulances screamed through the streets. Survivors picked through the rubble of their homes, salvaging clothes, furniture, family photos and financial records, the air pungent with the smell of gas and smoking embers.

Some neighborhoods were completely flattened and the leaves stripped from trees, giving the landscape an apocalyptic aura. In others where structures still stood, families found their belongings jumbled as if someone had picked up their homes and shaken them.

Kelley Fritz, 45, of Joplin, rummaged through the remains of a storage building with her husband, Jimmy. They quickly realized they would never find the belongings they stored there or much of what was in their home after the tornado ripped away the roof. Their sons, ages 20 and 17, both Eagle Scouts, ventured outside after the storm.

"My sons had deceased children in their arms when they came back," Fritz said. "My husband and I went out and saw two or three dead bodies on the ground."

The Joplin twister was one of 68 tornadoes reported across seven Midwestern states over the weekend, according to the National Weather Service’s Storm Prediction Center. One person was killed in Minneapolis. But the devastation in Missouri was the worst, eerily reminiscent of the tornadoes that killed more than 300 people across the South last month.

The National Weather Service’s director, Jack Hayes, says the storm was given a preliminary label as an EF4 — the second-highest rating given to twisters. The rating is assigned to storms based on the damage they cause. Hayes said the storm had winds of 190 to 198 mph, and at times, it was three-quarters of a mile wide.