About that Mariott Hotel attack in Islamabad

Reports on the news tonight that sophisticated bomb-enhancing material (powdered aluminum) was used to increase the effect of the blast. But I find this report also interesting:

Was there a top secret and mysterious operation of the US Marines going on inside the Marriott when it was attacked on Saturday evening? No one will confirm it but circumstantial evidence is in abundance.

Witnessed by many... a US embassy truckload of steel boxes was unloaded and shifted inside the Marriott Hotel on the same night...

Both the main gates (the entrance and the exit) of the hotel were closed while no one except the US Marines were either allowed to go near the truck or get the steel boxes unloaded or shift them inside the hotel. These steel boxes were not passed through the scanners installed at the entrance of the hotel lobby and were reportedly shifted to the fourth and fifth floors of the Marriott...

I know nothing about the reliability or biases of the source (Pakistan Daily), and the report offers no evidence other than hearsay, but it is interesting.