The gunman who fired on Dr. Aaidh ibn Abdullah al-Qarni a renowned international lecturer and author of many motivational books on Islam and Sheikh Turki Assaegh was shot dead by the men's security entourage at the Western Mindanao State University in Zamboanga.

Zamboanga City’s police spokesperson told reporters that the victims were shot while on board their vehicle outside the university gymnasium Tuesday night after al-Qarni gave a free lecture.

“We are investigating this incident” Senior Inspector Helen Galvez said adding that both men were rushed to hospital in Zamboanga a predominantly Christian city in the majority Muslim southern region.

Authorities have said that they have no idea how the gunman managed to evade university security and sneak in a .45-caliber pistol.

Al-Qarni was hit in his right shoulder left arm and chest while Assaegh was hit in his right thigh and left leg.

Witnesses who had attended the forum said several shots were fired at the Saudi nationals when al-Qarni opened a window of their vehicle to bid farewell to the seminar attendees.

Galvez also said that two suspects were placed in custody for questioning.

Police have yet to determine the motive behind the attack and investigations are ongoing to establish the identity of the slain suspect.

The Ulama Council of Zamboanga Peninsula said the forum -- which the Muslim group had organized -- attracted more than 8000 attendees from different parts of southern Mindanao island.

There was no immediate statement from the Saudi Embassy or the Philippines’ government on the attack.

Zamboanga Mayor Isabelle Climaco-Salazar has ordered police to thoroughly investigate the shooting and its motive.

The Philippines military is presently battling members of a Moro group (formerly known as the Khilafah Islamiyah Mindanao) with alleged ties to the Southeast Asian terror group Jemaah Islamiyah in the southern region.

In the past week at least 24 militants have been killed.

The militants are seeking to take advantage of the shelving of a law that would have sealed a peace process between the country's one time largest Moro rebel group and the government.

Moro Islamic Liberation Front Vice Chairman for political affairs Ghadzali Jaafar claimed last week that armed groups who have been engaged in clashes with government troops in the south since the beginning of the month are dismayed by the failure of President Benigno Aquino III's administration to pass Bangsamoro Basic Law.

BBL would have implemented a 2014 peace deal signed by the government and the MILF on Mar. 27 2014 -- encompassing the Framework Agreement on the Bangsamoro and the Comprehensive Agreement on the Bangsamoro -- bringing 17 years of peace negotiations in southern Mindanao island to a close.

However the agreement has been shelved during the duration of the country's presidential elections leading to fears that such "terrorist" groups may try and take advantage of local frustrations to move into the territory.