ATHENS, June 30 (Reuters) — Four people were trapped after a four-story apartment block collapsed on Tuesday in the Petralona area of Athens, the fire brigade said.

Firefighters and police were deployed to the area to help with the rescue operation which is ongoing, the service said in a statement. Footage on local media showed rescue workers walking amid the rubble.

It was not clear what caused the collapse of the building which hosted seven apartments. Construction work was underway in an adjacent building, local media reported.

The Lebanese activist Mona Khalil, who became a beloved figure in the country for a decades-long effort to protect a nesting site for turtles near her home, has died from injuries sustained in an Israeli strike.

Khalil, 76, ran a sanctuary called the Orange House Project near the Mediterranean city of Tyre. She hosted volunteers in her house to clean and monitor a mile-long beach and welcomed tourists to stay and learn about conservation.

An Israeli airstrike hit her house earlier this month, severely wounding Khalil, who was moved to an intensive-care unit in Beirut before succumbing to her injuries on Friday, according to friends. Her assistant, an Ethiopian woman, suffered burns but was recovering.

During the Lebanese civil war of 1975-90, Khalil moved to the Netherlands. She returned to her family's land in 1999, where she had a chance encounter one evening with a turtle digging a nest in the sand on the beach.

Khalil painted the house orange to match the national colour of the Netherlands, which she said had given her refuge during a time of need, and started a protection and ecotourism project for loggerhead and green sea turtles that nest along Lebanon's southern coast.

Foreign tourists had to coordinate their trip with the Lebanese military, as the bed and breakfast sat on land that Israel had repeatedly invaded and occupied. Those who managed to get permission would stay in Khalil's idyllic home, with its flower-lined courtyard often filled with rescued dogs and cats. It is just a short walk through banana groves to the beach.

Regular power cuts and a lack of air-conditioning meant some visitors left unfavourable online reviews, although most were glowing as Khalil provided what other B&Bs could not – a chance to witness and help hatching turtles and to take part in protecting their vulnerable populations.

Khalil's marine conservation efforts were initially resented by some local people, including property developers and fishers who used dynamite fishing, a practice she successfully fought against. Her house was also hit by Israeli bombardment during the 2006 war with Hezbollah.

Despite Israel's continued invasions, Khalil remained in her home. In a 2017 interview, she said she had not lost hope in turtle conservation and would continue indefinitely. "As long as God gives me life," she said.

The Lebanese wildlife conservation group Green Southerners mourned the loss of an environmental campaigner they said had inspired generations of Lebanese to value and protect their ecosystems.

"Her work made her one of Lebanon's most respected voices for marine conservation and biodiversity protection," the group said in a statement.

"Green Southerners strongly condemns the attack that claimed Mona Khalil's life and injured her assistant. The strike targeted a site that had long been known for environmental conservation, biodiversity protection, and public awareness. Her death stands as a stark reminder of the devastating toll that Israeli attacks continue to exact on civilians, environmental defenders, and the natural heritage they sought to protect."