on the take

With low wages comes low morale and an invitation to corruption -- Afghanistan's police are regularly accused of being on the take.

on the take----- illegally paid for favors

hard/hot on sb's heels
following someone very closely:
She ran down the steps with a group of journalists hard on her heels.

come/follow hard/hot on the heels of sth
to happen very soon after something:
For Walter, disaster followed hard on the heels of his initial success.

下面這一則新聞是三月16日cnn報導，
( Iran’s foreign minister made an unannounced visit to Saudi Arabia on Sunday )
Mottaki’s surprise visit comes on the heels of a summit Wednesday in Riyadh to improve relations and overcome contentious issues among Arab countries.

如果只是在一個事件後的話，in the wake of 也是一個很好的選擇。
Earlier Monday, a leading congressional player on financial issues called for a shakeup at AIG in the wake of the bonus disclosures.