It's seems like you don't use Twitter. Grab some popcorn and check @mycrypto and @myetherwallet channels on Twitter.

tl;dr Myetherwallet owners splited now there is two websites operated separately.

Which one is secure?

Virustotal shows mycrypto as phishing website (https://www.virustotal.com/#/url/420d7e7e680ed367bb64c679f6d8c08fe463c8db3f577c177567ef0bf2ba8368/detection), so I won't be using it. Original MEW seems to be safe but still be cautious.