Abu Dhabi police have arrested a woman for the stabbing death of American teacher Ibolya Ryan at a glitzy mall and say that she also planted a crude bomb at an American doctor's home.
Authorities in the capital of the United Arab Emirates say the victims were targeted based "on nationality alone and had nothing to do with personal issues."
"She aimed to create chaos, shake the security in the country, and terrorize people in the UAE," police said in a statement Thursday, adding that the woman confessed.
Saif Bin Zayed, UAE minister of the interior, said the suspect — seen in security footage fleeing the scene of the crime covered in black robes from head to toe — is an Emirati national in her late 30s. Her name was not released.
She allegedly knifed kindergarten teacher and mother of three Ibolya Ryan in a bathroom stall at the Boutik Mall on Reem Island on Monday afternoon, leaving behind a bloodied kitchen knife before she hustled into an elevator and out of the building.
“After committing the ruthless crime...the suspect moved to another location later that day to plant a primitive bomb in front of an Arab-American doctor’s home — a doctor who has dedicated his life to saving the lives of others," the interior minister said.
"One of his sons discovered the bomb while he was heading to the mosque for the sunset prayer. Security forces were able to dismantle the bomb at the right time before it was detonated.”
The bomb was made of small gas cylinders, a lighter, glue, and nails "to cause maximum injuries when detonated," officials said.

It's unclear how investigators were able to identify the suspect, who was fully cloaked in a traditional black robe, known as an abaya, and wearing gloves and a full face veil known as a niqab.
They had released surveillance footage of the woman — whom they dubbed the "Reem Island ghost" — entering the mall, heading to the restroom and then fleeing 90 minutes later.
A second video released by the Ministry of the Interior showed the robed suspect with a suitcase, and then a white car is shown driving away.
Heavily armed officers with bulletproof vests were then seen raiding a house with the same white car parked outside. Waving guns, they handcuff and lead a female out. The female's face is not shown — but further images show the same suitcase inside the car and a steering wheel covered in blood.
The attack on Ryan comes just weeks after the U.S. embassies in the Middle East warned citizens of an anonymous posting on a jihadist website encouraging attacks against teachers at American schools in the region.
Born in Romania to Hungarian parents, Ryan was living with twin 11-year-old sons in Abu Dhabi, the fourth country where she had taught in 15 years.
"She was a great person," said Karen Ryan, whose husband is the victim's brother-in-law. "She was so committed to her teaching."
Jack Chesnutt, Charlene Gubash and Julie Studer contributed to this report.