Some confusion here Rose.
They managed to shoot three people dead with those ‘billy clubs’.
No confusion at all.
The policy is that some British policeman are equipped only with nightsticks (or 'batons') while some others are armed with firearms.
I read or heard that the policy is in place because firearms are not deemed necessary most of the time and that the authorities don't want citizens to become alarmed about seeing too many police walking around with guns!
Apparently the first policeman to encounter a muslim terrorist last night was one of those unfortunates equipped with only a nightstick.
When he (she?) challenged the muslim terrorist he got severely stabbed and cut as a consequence of not being armed with a gun.