Car Alarms: Alarm-1998 Madza 626, alarmtek, dash area

Question
I recently bought a used 1998 Madza 626 w/o remote, did not know it had an alarm until the next day while sitting in the driveway the horn started honking, the lights flashing.I couldn't think of anything else to do so I got in and turned the key forward.It stopped.Everytime I lock it, this happens. I know nothing about alarms(whether factory or aftermarket)so my question is how can I disarm it? Where is it and what does it look like?

Answer
Please be more descriptive if possible.

"GOING OFF?"

I need to determine whether it's a factory alarm
issue or, if it's an aftermarket system you are
dealing with.

Is it: Headlights flashing, car horn honking
and a worded SECURITY" light in the dash flashing?
(doubtfull since none of the notes show this
car as having a factory alarm system)=FACTORY

Or,

is it: flashing parking lights,
an LED in the dash area, and a siren
going off?= AFTER MARKET

Let me know more on this to better
advise you on a course of action
to take.

Best Regards,

Robert Martin
CEO/ALARMTEK
CARALARMMAN.com