Mad/Sev: not so safe areas?

First time in Spain will be in April! I'll be starting in Madrid and then on to Seville....after that, who knows? Can anyone tell me which parts of Madrid and Seville you wouldn't recommend going to?! Which parts are known as not so good?

Thanks,

Nao

As for Madrid I would avoid the south of the city center, that is, Lavapies. It is much safer now than a year ago but I would still skip it. I would
not go to the area left to Chueca: Barco st etc..... specially at night.
I would stick to Huertas, El Madrid de los Austrias, Salamanca, these are some of the safest districts.

Regards,
A.J.