LOS ANGELES, July 24 (Xinhua) -- The heart of Yosemite National Park, one of the most visited national parks in the western U.S. state of California, will be closed in the coming days as firefighters are battling a fast-moving wildfire nearby, said authorities on Tuesday.

A huge wildfire, dubbed "Ferguson Fire," which started on July 13 in the Sierra National Forest, grew to 36,587 acres (148 square kilometers) by Tuesday morning with only 25 percent containment, according to the latest update from the U.S. Forest Service.

The core area of the Yosemite National Park, including Yosemite Valley, Wawona, and Mariposa Grove, will be closed at least from Wednesday to Sunday due to fire operations, read an alert issued by the park.

Tioga Road and Tuolumne Meadows, including Big Oak Flat and Tioga Pass entrances, and Hetch Hetchy will remain open.

Pictures on social media showed fires near the park choked the skies with smoke.

"#FergusonFire is having a substantial impact on air quality in Yosemite," tweeted the National Park.

More than 3,300 firefighters are battling the blaze on the scene. They are aided by 194 engines, 45 water tenders, 16 helicopters and 52 dozers.

Weather conditions could hamper firefighters in the coming days. Weather forecasts are calling for hotter and drier air throughout the week as conditions align for critical and extreme fire weather.

About 1,000 reservations will be canceled during the current peak tourist season due to the closure of the National Park, according to U.S. media reports.

Designated a World Heritage Site in 1984, Yosemite is internationally recognized for its granite cliffs, waterfalls, clear streams, giant sequoia groves, lakes, mountains, meadows, glaciers, and biological diversity. Some four million visitors flock to the park each year.