Story highlights Two men arrested after intensive weekend manhunt

Two boys, 7 and 10, and their sister, 15 were killed when a stolen SUV struck them

Two men carjacked a real estate agent's SUV and sexually assaulted her at gunpoint

Mother of three siblings remains in critical condition

Philadelphia police said Monday they've apprehended two suspects in a Friday carjacking that left three children dead and their mother in critical condition.

Jonathon Rosa, 19, and Cornelius Crawford, 22, are both charged with several felonies -- including three counts of murder, kidnapping, aggravated assault, sexual assault and more -- in a crime spree that began Friday morning.

Police said the duo carjacked a 45-year-old real estate agent at gunpoint and both sexually assaulted her as they drove around the city with her in the backseat of her SUV.

Homicide Captain James Clark said at one point the Toyota 4Runner blew a tire, which caused Crawford to lose control and careen into a street-corner fruit stand, striking and killing 10-year-old Thomas Reed, 7-year-old Terrance Moore and 15-year-old Keiearra Williams. They were all the children of 34-year-old Keisha Williams, who is still in critical condition, according to Giselle Zayon of Temple University Hospital.

The SUV then wrecked in a vacant lot, according to police, and the two men fled. They remained at large for most of the weekend, until Rosa, accompanied by his pastor and his mother, turned himself in Sunday evening "once he became aware that they were closing in on him," Clark said Monday. Crawford, a convicted felon, was arrested without incident, he said.

Police say Cornileius Crawford, 23, was the driver in Friday's carjacking in Philadelphia that left three children dead.

Jonathan Rosa is charged with three counts of murder stemming from Friday's carjacking in Philadelphia.

Philadelphia police conducted an intensive, around-the-clock manhunt for the pair over the weekend. "It was a great collaboration between police and the community," said Clark.

A message left Monday for the attorney of one of the suspects was not immediately returned.

The family, who lived just around the corner from the fruit stand, was working there Friday to raise money for a local garden, according to police.

"They were sweet," Ursula Jackson told CNN affiliate KYW . "They were beautiful, they were beautiful little kids."

Williams said Monday that former NBA star Charles Barkley, who spent part of his career playing for the Philadelphia 76ers, has offered to pay for the funerals of the three children.