Hasan al Askari

Assalamualikum,

I was reading on article relating to the current events in Iraq, where a Shi'a shrine was damaged.I quote:

"The tombs of Imam Ali Al Hadi (radi allahu anhu) and Imam Hasan Al Askari (radi allahu anhu) have been a place of great spiritual and religious significance. Both Imams hold a significant spiritual position in both Sunni and Shia schools and command the utmost respect and reverence from all believers alike."

I was wondering if this in fact true and the mentioned 'Imaams' hold any significance in Islam. I couldn't help but think of Shaykh Abdul Qadir Jilaani (ra) who was undoubtedly a great scholar, yet after his death, some people have elevated his status to a level of Shirk.

Jazakallah