MANAGUA, Nicaragua -- A magnitude-6.6 earthquake shook Nicaragua on Friday afternoon, sending people running frightened into the streets less than 24 hours after a magnitude-6.1 quake rattled the country, the United States Geological Survey said.
There were no immediate reports of new casualties or serious damage, but the USGS said the quake was felt in El Salvador and neighboring Costa Rica.
The government raised the number of people injured in the Thursday evening quake from 23 to 200. It also said that a 23-year-old woman had died of an apparent heart attack after the quake.
In the capital city of Managua, 300 homes were damaged and at least 20 were destroyed by the Thursday quake, said one of the mayor's deputies, Fidel Moreno.
Authorities ordered the demolition of two old buildings that had withstood the earthquake of 1972 that killed 10,000 people. Hospitals began discharging patients with minor illnesses so they could have beds available in the event of injuries from an aftershock or new quake.
"We're trying to take as many preventive measures as possible to prevent more deaths," said government spokeswoman and First Lady Rosario Murillo.
President Daniel Ortega said that he raised the country's alert level to red, meaning government officials were evacuating everyone at risk of harm from aftershocks or new quake.
On Thursday night, officials took 155 people out of neighborhoods northeast of the capital city due to risk of landslides. One of the shelters was still housing 22 families on Friday.
Schools closed in the capital and also in the northwestern city of Leon.
The government said roughly 800 homes were damaged in the town of Nagarote and surrounding areas, about 30 miles (50 kilometers) northwest of the capital.
Friday's quake struck at 3:29 p.m. local time (20:29 GMT), and was centered about 6 miles (11 kilometers) east-southeast of the town of Nandaime. It had a depth of 85 miles (138 kilometers).
The USGS said Thursday's quake struck at 5:27 p.m. local time (23:27 GMT), and was centered about 11 miles (18 kilometers) southeast of the city of Larreynaga. It had a depth of 6.2 miles.