Toyota Repair: leaking oil & water, freeway drive, toyota camry

Question
hi, we have a toyota camry 2000 automatic transmission with 155K miles. on the way home after a long freeway drive as we came to a stop the car started making a loud rattling noise, it sounded like a loud motorbike idling. when we stopped we noticed it was leaking copious amounts of dark liquid, and the engine was smoking a bit. when we looked on the ground the liquid appeared to be water and oil. the oil was last changed and the vehicle examined aprox 6 months ago. what are the possible things that might be wrong? what would you recommend we do about this to check further options and/or to save money? thank you sooooo much! brenna

Answer
A noise like that is never good news, it sounds like the engine lost oil pressure, possibly the oil filter started to leak, has the oil level been checked, is there any oil in the engine? Another possible problem is that the water pump failed causing the timing belt to break(this is a 4cylinder, correct?) if not let me know.  What does the engine do now when trying to start it, does it run or try to run?