Fire rescue personnel came to the aid of four hikers in separate instances Sunday.

Rescuers were called to the Manana Trail near Pacific Palisades at about 9:15 a.m. to help a 52-year-old man who had slipped on a root and injured his knee, Capt. Carlton Yamada, Fire Department spokesman, said. The man was flown from the trail and taken to a hospital.

A woman in her 60s was flown from Diamond Head Summit Trail at about 11:15 a.m. after becoming dehydrated during a hike. The woman, a visitor from Japan, just wasn’t prepared for the hike, Yamada said.

About three hours later, another woman, this one in her 50s, suffered heat exhaustion while hiking up the trail. A fire helicopter brought her down to a nearby park.

Shortly after noon, firefighters were called to Palolo Valley, where a male hiker had hurt his ankle when he slipped down a 20-foot embankment. Rescuers flew him from the trail in the early afternoon.