Allentown Police are asking Amy Yu to contact her mother and brother.

Yu, 16, of Allentown, and Kevin Esterly, 45, of Lowhill Township, are believed to be in Mexico.

Allentown police and Lehigh County District Attorney Jim Martin held a news conference 3 p.m. March 16 during which Capt. Bill Lake of the Allentown Police Department gave a brief timeline for the teen’s disappearance, asked the public to remain engaged in the search for her, and issued a direct appeal to the teen.

“Your mom and brother are worried and miss you,” Lake said. “They want you to come home.”

He urged Yu to go to a worker at one of the resorts, to a member of law enforcement in Mexico or to contact her mother through email, texting or social media.

Yu was listed as a runaway after her mother, Mui Luu told police her daughter failed to return home from school on March 5.

According to Lake, police were initially told Amy had boarded her school bus that morning, and that she had traveled to her charter school in Northampton County.

Based on that information, Allentown Police had been working with and assisting the Colonial Regional Police Department, which has jurisdiction over the Lehigh Valley Academy Regional Charter School, where Yu is enrolled.

Through investigation it was subsequently learned Amy never boarded her bus that morning.

On March 7, Allentown Police took a missing person’s report on Esterly, from a family member, and Esterly was listed as missing or endangered.

That same day, an arrest warrant for Esterly was obtained by Detective Andrew Hackman, the lead investigator, charging Esterly with interference with the custody of a child, a felony of the third degree.

Accoring to Lake, investigators believe Yu left Allentown willingly with Esterly.

On March 7, police received credible information was received indicating Yu and Esterly obtained one way plane tickets, and had flown from Philadelphia International airport via the Dallas/Fort Worth airport, to Cancun, Mexico, during the evening hours of March 5.

Lake noted their flight to Cancun, occurred at approximately the same time Yu’s mother was reporting her as a “runaway” to the Allentown Police.

“The Allentown Police Department has received numerous tips from the public as a result of the media attention that this case has generated,” Lake said. “We very much appreciate the assistance provided by the public and ask that the public remain engaged as law enforcement continues to search for Amy Yu and Kevin Esterly.

“We are asking that the media relay a message to Amy that her mom and brother miss her very much, as do her classmates and friends,” Lake said. “Everyone is very worried about you, Amy, and everyone wants you to return home safely.

“Amy, if you are uncertain how to come home or who to contact for help, you may simply reach out to a law enforcement official, a resort staff member, or contact your mom via text message, email or social media, and we will work to reunite you with your family right away.”