It may help you to check with your local police to see if there are any media releases that involve your tenant. Here is an example of the Toronto Police media release page:

If you are not able to gather more information about why the property was raided by police, then you should concentrate on giving an N5 for damage to the property and an N4 for nonpayment – either under the door of the unit or by mail. If serving notices by mail, you have to add 5 days to allow for mailing. 

To get a clear picture of the amount of damage that was done, you should give 24 hours’ written notice to enter to do a maintenance inspection with a contractor or handyman who can give you an estimate of costs.

The N4 is a 14-day notice to pay the rent or move out by the termination date. You can apply on an L1 application on the next available weekday after the termination date.

The N5 is a 20-day notice to vacate for damage or disturbances. The form gives the tenant 7 days to fix or pay for the damages. On the 8th day you can apply on an L2 application for eviction for the reasons on the N5.

5 days must be added to the termination date if the notice is being sent by mail.

You may combine applications and pay the Landlord and Tenant Board only one fee of $201. If they are filed separately, you will have to pay twice.