premise: Philippine police detained Thursday a former defence secretary who had declared himself president and urged the armed forces to withdraw their support for President Gloria Arroyo.
  Retired general Fortunato Abat, 80, was bundled into an unmarked police van and taken in for questioning with two other members of his self-proclaimed cabinet to face possible charges of inciting sedition, the authorities said.
  There was no indication that either the military or the public were taking Abat's call to overthrow Arroyo very seriously, although rumours of a coup plot have been rife for weeks in Manila.
  "There can only be one president," said police spokesman Leopoldo Bataoil.
  Though the government had considered Abat more of a nuisance than a security threat, Arroyo's chief aide, Executive Secretary Eduardo Ermita told reporters: "We have to do something because we cannot let the people feel there is a violation of law and nothing is being done."
   What does "bundled into an unmarked police van" refer to?
hypothesis: Philippine police detained Thursday a former defence secretary