The Metropolitan Police searched the River Thames after Dan Evans admitted he dumped phone-hacking mobiles into the water, a court has heard.
During his time at the Sunday Mirror, Evans said he disposed of ten pay-as-you-go handsets in the River Thames nearby.
Defence lawyer Timothy Langdale QC said divers have since searched the stretch of river where he said he threw the phones.
The Old Bailey also heard that two untraceable pay-as-you-go phones acquired after he joined the News of the World in 2005 were "smashed up and binned" because in Wapping the river was too far away.
Evans said he needed a safe phone for investigative work "dealing with hitmen, people stealing dodgy stuff – serious investigations – people who did not think in terms of 'I will go to my lawyer', more 'I will stick you in a van'."
Asked by Langdale how many hitmen he knew, Evans said: "One."
He said it was "crass stupidity" when he was caught out not using a safe phone.
Earlier Evans told the court that he turned to drink and drugs to cope with the stress of working as a tabloid news reporter.
He said he would “self-medicate” because of the amount of phone-hacking he was expected to do.
According to Evans, he started drinking and taking drugs while at the Sunday Mirror before joining the News of the World in 2005.
"I was self-medicating. I was depressed, not happy and not coping. It is not uncommon to deal with stress in different ways. For me the initial release was having a drink after work."
On the link with hacking, he said: "The secret made me unhappy. Carrying an enormous secret and delving into the lives of people who did not deserve it made me unhappy."
Evans, who said he had been in therapy for the last year and a half, said he joined the News of the World for the opportunity to run his own investigations unit.
He recalled: "I wanted to start afresh and do something on my own terms," adding: "I was out of the frying pan into the fire but I was pretty young. I made mistakes."
Langdale asked Evans if he had been hired by the News of the World because of his hacking expertise, he replied: "You could say that," but added that he was not defined by the single act alone.
Asked by Langdale why he did not just leave the News of the World if he was so unhappy, Evans said: "I didn't want to be turned away with my tail between my legs. I wanted to be a success at it. I became a father. I was too worried about money. (A senior NoW journalist) knocked my confidence pretty hard."
Langdale suggested there was nothing to stop him leaving, but Evans said: "There's nothing to stop me jumping off a bridge but I didn't do that."
Evans insisted hacking was an "open secret" in the office.
"I was conscious that what I was doing was wrong. It was widely known, it was widely held this was going on.
"Other reporters asked me to do things on their behalf, usually at the behest of the desk."
Pressed on the subject again, he repeated: "I did not broadcast it because that would have been crass but everybody knew."
Raising his voice slightly, Evans said: "The truth is that Andy Coulson knew exactly what was going on on his watch."
At the moment of Evans's declaration about Coulson, the defendant and witness stared at each other across the courtroom.
Evans was caught because he used his own phone for hacking, the court heard.
Asked why he did not raise the question of security amid the pressure to keep expenses down, he said: "There is a part of me that's thinking 'you don't want to be careful, why should I be careful either'?"
All of the defendants deny all of the charges.
The case continues.