#YesAllWomen: The most important thing you will read on social media all day.

TRIGGER WARNING: This article includes graphic descriptions of violence and may be triggering for some readers.

The weekend massacre by 22-year-old Elliot Rodger in California has sparked a massive reaction on social media with the hashtag #YesAllWomen trending on twitter overnight.

Last night, a bizarre 137-page manifesto in which Rodger detailed his plans for the killings was published by the LA Times.

In the graphic violent document he wrote of his “War on Women”.

“I will punish all females for the crime of depriving me of sex,” he wrote.

“They have starved me of sex for my entire youth and gave that pleasure to other men. In doing so, they took many years of my life away.”

Shortly before the attacks, Rodger posted an online video on YouTube railing against women.

In three months prior to the attacks, he uploaded 21 YouTube videos – all expressing his anger at being left out from what he saw as his ‘right’ to sex, women and pleasure.

The killer is now known to have spent vast amounts of time on ‘Men’s Right forums’ on the internet, expressing misogynistic views. He ranted about how society was to blame for what he saw as his failures to connect with women.

The #YesAllWomen hashtag began trending overnight in response to some social media users who had started to support Rodger’s justifications for the murder of six people. The feminist online community decided to band together and started the #YesAllWomen hashtag.

The first tweet was from a @gildedspine who wrote, “I’m going to be tweeting under the #YesAllWomen hashtag. Let’s discuss what ‘not all men’ might do but woman must fear.”

The hashtag took off.

Meanwhile, several other hashtags began offering differing opinions, including #NotallMen.

The #YesAllWomen hashtag has had over 250,000 tweets in 24 hours and continues to trend on Twitter.

Meanwhile, CNN reports that while Rodger was carrying out his murderous rampage, his parents were desperately searching for him.

Rodger sent several people — including his parents and at least one of his therapists — the 137-page manifesto outlining what he was planning to do via e-mail not long before the shootings began.

Simon Astaire, a family friend, told CNN that Rodger’s mother, Lichin, immediately went to Rodger’s YouTube page, where he had been known to post videos about himself. According to Astaire, that’s when Rodger’s mother saw her son’s latest video called “Retribution” that he posted Friday, the day of the shootings.

CNN reports, “His mother called Rodger’s father, Peter, and said he had to watch the YouTube video.”

“At the time, Peter Rodger had not yet seen the manifesto. Lichin Rodger called 911 and the parents set off for Santa Barbara from Los Angeles, according to Astaire. En route, they heard there was a shooting. Later that night, they found out their son was behind the violence.”

Here are some more of the tweets sent using the #YesAllWomen hashtag.