Police will resume their search for Nicole Mittendorff from Woodbridge, Va, April 18. (WUSA9)

The search for a missing Fairfax County firefighter widened Monday afternoon from the location where her car was found parked in a remote section of Shenandoah National Park, park officials said.

The Virginia State Police and U.S. Park Police were using officers trained in search and rescue, dogs and aircraft to try to locate Nicole K. Mittendorff, 31, of Woodbridge, who was reported missing on Friday, police said.

The search on Monday morning had centered on the White Oak Canyon Trail, near where Mittendorff’s cream-colored 2009 Mini Cooper was discovered on Saturday close to the popular hiking spot of Old Rag mountain, said Corinne Geller, a Virginia State Police spokeswoman.

But on Monday afternoon, Shenandoah National Park announced it was closing four other trails in the area to search for Mittendorff as well.

Separately, St. Paul United Methodist Church in Woodbridge, Va., was planning to hold a prayer service for Mittendorff at 7:30 p.m. on Monday night. The event will be open to the general public.

Nicole Mittendorff is seen in an undated family photo. She was reported missing on April 15 and her car was found in rural Virginia a day later. (Family photo)

Geller declined to comment on whether anything was found inside Mittendorff’s car that would give any indication about what happened to her or where she might have gone.

Mittendorff’s father wrote in a Facebook post that she is an avid runner and triathlete and may have gone to the location to train for a race. Geller said police have no reason to suspect foul play at this point.

“It’s a fairly expansive search,” Geller said. “It’s not a field where you can do a grid search. It’s mountainous terrain.”

Robert Clardy, Mittendorf’s father, wrote on Facebook that Mittendorff was last heard from on Wednesday morning. Her last contact was a text message that came around 10:50 a.m. Her last known location was in Warrenton, Va.

“She is extremely dedicated to her job and didn’t show for a Friday morning changeover,” Clardy wrote on Facebook.

Geller said Mittendorff’s husband, whom she identified as an employee of the Virginia State Police, first reported her missing. Steven Mittendorff is listed on an online profile as a first sergeant and the area commander for the Arlington Field Office for the VSP.

The family has set up a Facebook page and Web page to aid in the search for Nicole Mittendorff.

“I wanted to take a moment to thank everyone who has viewed, liked, and shared this page dedicated to finding my wife,” Steven Middendorf wrote on Facebook. “I am overwhelmed by the number of calls, texts, and social media messages that I have received, but have not been able to answer.”

Jennifer Clardy Chalmers, Mittendorff’s sister, told The Post on Sunday that Mittendorff is a career paramedic/firefighter with Fairfax County Fire and Rescue and has been with the department since 2013. The department directed questions to Virginia State Police.

“We are holding up as best as can be expected under difficult circumstances,” Chalmers said. “At this time we are focused on finding Nicole and have the deepest appreciation for everyone helping. We hope and pray for a safe resolution in the near future.”

Mittendorff is described as a 5-foot-6-inch white woman with blond hair and green eyes, weighing about 125 pounds. The Virginia State Police has asked anyone with information about Mittendorff to call 703-803-0026 or email information to questions@vsp.virginia.gov.