STORY: They departed from a planned evacuation point to Ukraine-controlled territory, two Reuters witnesses said.
Pensioner Tamara, 64, said she was going to stay with her sister in Ukraine's Zaporizhzhia. She was leaving the city with her husband, daughter, son-in-law and grandson.
"We need a break after the shelling, after all this nightmare. We lived in basements for 30 days," she said tearfully, as she waited to get on the bus.
Mariupol Mayor Vadym Boichenko, who has left the city, said about 100,000 civilians remained in the city on the Sea of Azov and that tens of thousands had been killed there since Russia invaded. The numbers could not be verified by Reuters.
Those still living there have been without power, heat and supplies for weeks, local authorities say. Deputy Prime Minister Iryna Vereshchuk described the situation earlier on Wednesday as "catastrophic".