BELLVUE, Colo. — Massive wildfires in drought-parched Colorado and New Mexico tested the resources of state and federal crews Monday and underscored the need to replenish an aging U.S. aerial firefighting fleet that is needed to combat a year-round fire season.

Wyoming diverted personnel and aircraft from two fires there to help with a 60-square-mile wildfire in northern Colorado. Canada also loaned two aerial bombers to fight the blaze following the recent crash of a U.S. tanker in Utah. And an elite federal firefighting crew arrived to try to begin containing a fire that destroyed at least 118 structures.

All told, about 600 firefighters will be battling the fire some 15 miles west of Fort Collins by Tuesday, said incident commander Bill Hahnenberg. “We are a very high priority nationally. We can get all the resources we want and need,” he said.

But Colorado’s House congressional delegation demanded that the U.S. Forest Service deploy more resources to the fire, which was zero percent contained and forced hundreds of people to abandon their homes. One person was missing.

In a letter to the Forest Service, Colorado’s congressmen said the need for firefighting aircraft was “dire.” Colorado U.S. Sen. Mark Udall urged President Barack Obama to sign legislation that would allow the Forest Service to contract at least seven large air tankers to add to its fleet of 13 — which includes the two on loan from Canada.

One of the region’s most potent aerial firefighting forces — two Wyoming Air National Guard C-130s fitted to drop slurry — sat on a runway in Cheyenne, 50 miles north of the Colorado fire. The reason: The U.S. Forest Service, by law, cannot call for military resources until it deems that its commercial fleet is fully busy. It also takes 36 hours to mobilize the crews and planes, officials said.

“They just haven’t thrown the switch yet because they feel like there are adequate resources available,” said Mike Ferris, a spokesman for the National Interagency Fire Center in Boise, Idaho.

Forest Service spokesman Steve Segin agreed.

“Right now, the fire manager on the incident feels that’s enough, that’s everything they need,” Segin said.

In New Mexico, firefighters got new air and ground support to battle a fast-moving wildfire that charred tens of thousands of acres and forced hundreds of residents to leave their homes in the southern part of the state.

Smoke filled the air in the mountain community of Ruidoso as evacuees gathered at a high school gymnasium to get an update on the lightning-sparked fire in the Sierra Blanca mountain range. The blaze exploded over the weekend and reached more than 54 square miles by Monday.

An estimated 35 structures have been damaged or destroyed by the blaze, and fire managers expect that number to grow once damage assessments are done.

Elsewhere in New Mexico, firefighters made slow progress against the largest wildfire in state history. The blaze has charred 435 square miles of forest since it was sparked by lightning in mid-May, and was 37 percent contained Monday.

Arizona’s state forestry division dispatched two water tenders and 15 fire trucks to New Mexico, which also welcomed the arrival of a DC-10 jetliner that can lay a 100-yard-wide, mile-long line of retardant or water.

At least 18 large wildfires are burning in nine U.S. states, forcing the reshuffling of fire crews and aircraft.

Ten tankers, large and small, were fighting the Colorado blaze.

“We knew at this point resources could get very short for us due to the amount of fire activity in the area,” said Beth Hermanson, spokeswoman for a team fighting a 13-square-mile fire in Wyoming’s Medicine Bow National Forest. That team sent air support to Colorado over the weekend. “You sort of have to be creative,” Hermanson said.

U.S. Forest Service Chief Tom Tidwell has long insisted the federal government has enough resources to respond to a year-round wildfire season driven by drought, heat, decades of fighting forest fires rather than letting them run their natural course, and bark beetle pine tree kill.

“We have enough resources at this time to be able to deal with the fires we currently are dealing with and what we expect to have to deal with the rest of this fire season,” Tidwell told The Associated Press last week. He emphasized that the forest service has the authority to transfer funds from other accounts to meet firefighting costs in any given year.

Some 1,459 square miles have burned across the country this year — less than the same period in 2011, when 6,327 square miles burned.