Teen jihadist Jake Bilardi described Boxing Day shoppers in Australia as "talking pigs" and said living in his own country made him want to behead people, a new cache of blog posts has revealed.

The dozen or so online missives by the young Melbourne man, who is believed to have died in an Islamic State (IS) suicide bombing on Wednesday, shows a disdain for the country he left to join the war in Syria and Iraq.

The new blog posts, all written under his adopted name, Abu Abdulla al-Australi in January and February this year as he waited in Ramadi, Iraq, to be sent on a suicide mission, also include tips for young jihadists transitioning into life in Iraq, appalling condemnation of the Pakistani female education activist Malala Yousafzai, and a vivid description of life in an urban war zone.

They emerged as an Iraqi military spokesman said the suicide bombing in which Bilardi reputedly took part was wasted because it had only injured a few soldiers, and that Australians should resist IS attempts to lure foreign fighters.

Under a photograph of shoppers pictured in Bourke Street mall, Bilardi wrote on January 15 the caption: "The talking pigs of Melbourne, Australia in their sty," then described Australia as "a land full of such filth and corruption that no one in their right mind could live there without a craving to let some heads roll".

It confirms the hatred he felt for the country of his birth, after the revelation this week that he had planned to attack cafes, shopping centres and consulates in Melbourne with knives, bombs and grenades. Police have confirmed that bomb-making materials were found in his house after he left to travel to Iraq.

In one post written by Bilardi on January 19 under the headline, "Let them feel our pain", he praised Australians Abdul Numan Haider, the "18-year-old lion" who was shot after attacking two policemen in Melbourne's Endeavour Hills in December, and Man Haron Monis, who was killed after a 16-hour siege at Sydney's Lindt cafe.

Bilardi urged others in Australia to rise up in a similar way using knives, saying Haider and Monis had already "terrorised every kafir [non-Muslim] on Earth".

"Yet the Muslims should never think that this is enough, we must be relentless, never allowing these pigs a moments [sic] rest, keeping them up at night with the legs trembling in fear, wondering if they're [sic] house is next".

In another post on January 22, Bilardi commented on Ms Yousafzai, the young Pakistani woman awarded the Nobel Peace Prize after she narrowly avoided being killed by Muslim radicals. Bilardi describes her as a "filthy American prostitute" and a "dog" who, despite the operation to execute her "is still barking".

"She is nothing but a murtad [Muslim born person who rejects Islam] who deserves at the very least 10 bullets in her head."

On January 16, Bilardi offered a vivid, blow-by-blow description of the battle in Ramadi, in which he described ducking sniper fire and dodging bodies in the street. The blog post described the street-by-street fighting in the city as a "stalemate" that could "end as a bloody war of attrition".

Foreshadowing his own apparent death in a suicide mission less than a month later, he wrote: "With a current waiting list of 12 martyrdom bombers, of which I am one, the Islamic State has the opportunity to launch large assaults and make big gains."

In another blog post he offered practical advice to new recruits, warning that the main barriers to fighting with Islamic State were psychological, that physical fitness was overrated, and that it was dangerous to grow too close to your fellow fighters in case their spirits were dejected when they died. He described his own spirit falling "to unbelievable depths and I began to feel completely hopeless" after a failed mission in the town of Baiji.

The uncovering of new posts comes as the spokesman for the Iraqi military said Bilardi's alleged suicide bombing failed to achieve anything. General Tahssin Ibrahim told ABC the assault on the 8th Army Brigade resulted in no fatalities and had little to no impact on Iraqi forces.

"This guy, he never do anything. He just kill himself," General Ibrahim said. "On our side ... he just destroyed some cars and injured little soldiers."

Bilardi is thought to have been a part of a co-ordinated campaign of suicide missions across Ramadi, west of Baghdad, on Wednesday.

The Australian government has been unable to verify Bilardi's death, but yesterday confirmed authorities cancelled his passport in October, two months after the teen left Melbourne for Iraq.

Meanwhile, Iraqi military spokesman General Ibrahim today said he had a strong message for Australians considering joining Islamic State militia: "Think about your family, please, please think about that. Don't do anything and put yourself in the hell without any reason so this is my notation for young Australian people," he told the ABC.

General Ibrahim said foreign fighters were being recruited with the promise of reaching paradise, but this was "stupid". Many of the suicide attacks in Ramadi on Thursday were carried out by foreign recruits.

with Allison Worrall