Witnesses said that two men had been been seen in the neighbourhood before
Mary Christine Balagtas innocently opened her door to what she thought were two delivery men, but was shot in the head at point blank range.
Her killers allegedly fled on a waiting motorbike after putting a bullet through her skull, according to local police.
The 23-year-old, who lived in the Phillipines, died in the ambulance on the way to hospital despite paramedics' best efforts to save her.
Superintendent Julio Lizardo, from Plaridel Police, confirmed they were investigating an ex-boyfriend of the student.
He said: "We believe the attack could have carried out by a hired gun.
"We found an empty shell from a.45 calibre pistol at the scene and believe that two men had fled on a motorcycle.
"Witnesses said that two men had been been seen in the neighbourhood before the shooting.
Mary Christine Balagtas innocently opened her door to what she thought were two delivery men
"Mary died in the ambulance on the way to the hospital. We are following several leads including a man who had a romantic relationship with Mary."
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You will be always in our hearts
Herlie Rozelle Flores Vecina
She had been studying at the University of Regina Carmeli College when she tragically died.
Her shocked colleagues have paid tribute to her on social media.
She had been studying at the University of Regina Carmeli College
Nicknamed 'Tin', friend Herlie Rozelle Flores Vecina said: "Life is just really too short for the family and friends you have left. We may not even know what true happened to you but we let it given in the hands of our almighty God.
"We are confident that justice will prevail. We just pray that your family and us, your friends will get that fair.
"Tin, you will be always in our hearts. You, as a daughter, a sister, a seatmate in elementary, a classmate on high school, a colleague on college… but most importantly, a friend. We hope to never forget you.
"We will sincerely miss you. We love you, Mary Christine. May you rest beautifully in peace, our dear friend."
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