Two 21-year-olds were charged Saturday with capital murder in the shootings of two Houston cab drivers, killings that sent shockwaves through the community and brought calls for extra protective measures for taxi drivers.

Danielle Rene Hudson and Chaz Omar Blackshear were arrested late Friday and admitted to the robbings and shootings, Houston Police Department spokesman John Cannon said.

The Houston couple is scheduled to appear in court Monday.

Grieving relatives described the victims — 32-year-old Mohammed Nabiil Elsayed and 50-year-old Blaise Uzoma Nwokenaka — as devoted family men with strong work ethics.

Nwokenaka's family members called the killings "beyond belief."

"It's amazing two people so young could be motivated by money and greed to not only rob him and kill him, but set him on fire. This is not just what they did to a cab driver. This is what he did to our family. We will never, ever, ever forget what they did," said his niece Charlene Nwoke.

Both victims were independent contractors for Yellow Cab, killed within two days of each other after picking up late-night fares at the same southwest Houston gas station.

Elsayed, an American by birth and of Egyptian heritage, was a night-time cabbie who until a few months ago taught Arabic language and culture to U.S. soldiers headed to the Middle East, said his uncle, Ahmed Ahmedaly.

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He was an especially quiet man who defined himself by providing for his family, which included 2- and 7-year-old daughters. He was also pursuing an engineering degree.

"He was just the simplest person you could meet. All he wanted to do was work, provide for his family and make their life as best as possible," his uncle said. "Nobody believed it. It was just shock. He's 32 years old, he left to go to work at night like he does every night and never came back."

He was shot in the head and chest around 2 a.m. Tuesday. His body was dumped in a drainage ditch in Acres Homes, and his cab was abandoned in the 12100 block of Overbrook in far west Houston, near where he had earlier picked up passengers.

Elsayed's uncle said: "We plan to be very involved in the upcoming trials, and we're going to do everything we can to make sure they get the death penalty."

Family 'destroyed'

Nwokenaka, a naturalized U.S. citizen who moved from Nigeria in the 1980s, had been driving 15- to 18-hour days for some 12 years — earning $150 to $300 daily — to support his two sons and three daughters.

He was a gentle man who held a master's degree in criminal justice and had worked in the past as a probation officer, said his cousin Charles Nwokenaka.

"He was a very humble, generous man. Everyone in the Nigerian community loved him," his cousin said. "This has destroyed his family."

The family is struggling to collect about $14,000 to bury Nwokenaka in Nigeria.

Nwokenaka was killed two days after Elsayed. He was shot three times in the back, and his cab was set on fire, his body still strapped inside.

A police officer patrolling the area noticed smoke coming from a parked cab in the 12100 block of Overbrook around 4:15 a.m. Nwokenaka was dead.

Yellow Cab 'relieved'

Police have not said who pulled the trigger in either killing but are expected to provide more details about the cases at a news conference Monday.

Roman Martinez, president and CEO of Texas Taxi, parent company of Yellow Cab of Houston, said in a prepared statement that local cab drivers are thankful for the quick arrests.

"We are deeply grateful to the Houston Police Department for working so diligently and quickly to get these murderers off the streets," he said. "The independent contractor drivers are relieved, as we are, to know the murderers who were preying on Houston's taxi drivers have been arrested."

Past convictions

Hudson's criminal background in Harris County includes convictions for theft in 2010, 2007 and 2006, for which she received a total of 110 days in the county jail, according to court records.

She also was convicted in 2008 for escape while under arrest, for which she received a sentence of one year in jail, and in 2006 for unauthorized use of a motor vehicle, for which she received 90 days.

Hudson identified herself as a native of Kansas on her Facebook page, where her most recent posting on Oct. 1 included the rap lyric: "Ain't no such things as friends, only associates. So if you run up on me I'm pullin' my gun out of my holster."

Blackshear, described by a friend as an aspiring musician, had a conviction in Harris County for marijuana possession in August. He received 10 days in jail, according to court records.

Ariel Alexander, a friend and Blackshear's former roommate, was shocked to learn of the arrests.

He said the two are "very mild-mannered people" with whom he always felt comfortable.

"I wouldn't think that they would ever do anything like that," he said. He described Hudson as a "sweetheart."

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