Immigration and Customs Enforcement agents search undocumented immigrants before placing them aboard a plane that will take them back to El Salvador. (Luis Sinco / Los Angeles Times)

Henry Fuentes closes his eyes and tries to sleep. But he can't. He is restless. He looks out the airplane window. This may be the last time he sees the United States. In less than three hours, he will land in El Salvador, a country he hasn't seen in eight years.

Fuentes hadn't planned on returning.

Immigration agents arrested him at his Houston apartment last month. Now the government was flying him and 115 other illegal immigrants back to Central America. Some had just crossed the border. Others, like Fuentes, had spent years in the United States and held jobs, owned cars and started families.

Like Fuentes, most of the deportees have mixed feelings about being sent home. They are angry about being deported but relieved to be out of detention. They are excited to return to their roots but frustrated by the country's lack of work. They are anxious to be reunited with relatives in El Salvador but distraught about leaving spouses and children behind in the U.S.

"It's very, very hard for me," Fuentes said as he leaned his head back against the seat. "I feel bad, very bad. I feel happiness because I am going to see my children again. I haven't seen them in eight years. But I feel sadness because I left my children behind."

The federal government has stepped up its immigration enforcement in recent years, resulting in record numbers of detainees. Authorities are trying to free up bed space by deporting illegal immigrants quickly and efficiently.

Their primary tool is a fleet of planes used to send home nearly 72,000 illegal immigrants, including about 14,100 criminals, to Central and South America in the 2007 fiscal year. That compares with 50,000 immigrants, including about 9,600 criminals, removed the year before. Authorities said they plan to arrest, detain and deport even more illegal immigrants this year.

The government has ended the practice of "catch and release" and instead is focused on "catch and return," said Michael Pitts, chief of the flight operations unit for U.S. Immigration and Customs Enforcement.

"It's a one-way airline," Pitts said.

Fuentes' journey began late on the night of Feb. 19 at a detention center in Willacy, Texas, when guards told him he was being deported. Early the next morning, Fuentes boarded a bus.

About 7 a.m., his bus pulled alongside a Boeing 737 parked at an otherwise empty airstrip in Harlingen, Texas. ICE Agent Josie Alvarado came aboard, holding a red pen and a clipboard.

"Good morning," she said loudly in Spanish. "You are going to El Salvador. When you get off, put your hands on your head. When we are on the plane, respect the authorities, and we will respect you."

No convicted criminals or gang members were on the flight. They are deported separately.

These deportees get some sympathy from the immigration agents. "We don't treat them as criminals. We treat them as compassionate as we can," Frank Filippone, the ICE officer in charge during the flight, said before leaving Texas. "They are here to make a better life for themselves or to send money back."

That's what motivated Fuentes to leave his family and pay a smuggler $6,500 for the months-long and dangerous trip north through Guatemala and Mexico and across the border. He had divorced his wife and spent his savings fighting for custody of his two children, Denisse, 3, and Harold, 2. He won, put them in the care of his parents, and went north to earn money to support them.

In Texas, Fuentes worked as a machinist, earning about $100 a day. Each month, he sent home about $500. "I want my children to be professionals," he said. "Earning $5 a day in my country, I couldn't do that. That's why I came."

But a few years after settling in Houston, he met and married a Colombian woman who has a green card as a legal U.S. resident. Fuentes became stepfather to her daughter, Natalie, and the couple had a son, Sebastian. Both children are U.S. citizens by birth.

For several years, Fuentes had temporary legal status that was granted to many Salvadorans. But on the morning of Jan. 10, immigration agents showed up at his door. They told him he had a deportation order for failing to appear at an immigration court hearing in 2006. Fuentes told them he had moved and never received the notice.

"I always tried to be responsible, very responsible in my life, you know, because I have children," he said as he sat aboard the flight.