NORTH TEXAS (CBSDFW.COM) – Earlier this week a Kennedale High School teacher was arrested and now two more North Texas teachers have been arrested for having sex with their students.

Christian Flores, a 27-year-old North Garland High School teacher and coach, turned himself in to Garland police after a warrant for his arrest was issued for having an improper relationship with a girl under the age of 17.

Flores is accused of having improper contact with the girl on a number of occasions. “Over 20 times, approximately 25 times,” said Garland police spokesman Joe Harn. “And at the time of the incident the student was 16-years-old.”

Police and educators in Garland are concerned there could be more victims. “They think there may be a possibility, yet they’ve not turned up anyone as of yet,” said Harn. “However, that’s one of the reasons we’ll let the public know, let the students know. Where as, if that has happened we’re asking that those students or parents come forward.”

Thursday night April Alexander, a 26-year-old former high school biology teacher, was arrested in Irving. “During this investigation we learned that Mrs. Alexander, it was alleged she had sexual relations with a student, who was one of her students at MacArthur High School,” explained Irving Police Department Spokesman John Argumaniz.

The teacher and student, who was 16-years-old when the relationship started, allegedly had sex more than 25 times.

According to Argumaniz, Alexander resigned from the school in November of 2010.

Both Flores and Alexander have bonded out of jail.